HS Sample Set 5, Round 13 from NSB
Which of the following statements BEST describes whether or not the magnitude of the standard deviation depends on the location of the center of the data? W) Yes, the larger the mean, the larger the standard deviation X) Yes, because you have to know the mean in order to calculate the standard deviation Y) No, standard deviation is not affected by the location of the center Z) No, standard deviation only measures how values differ from each other and not how they differ from the mean
W: W) Yes, the larger the mean, the larger the standard deviation
X: X) Yes, because you have to know the mean in order to calculate the standard deviation
Y: Y) No, standard deviation is not affected by the location of the center
Z: Z) No, standard deviation only measures how values differ from each other and not how they differ from the mean
Answer: Y) Y) No, standard deviation is not affected by the location of the center
What is the minimum value of the function f(x) = x ln(x)?
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Which family of genes, present in all metazoan organisms, is instrumental in specifying the anterior-posterior axis and segment identity during early embryonic development?
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By name or number, identify all of the following four actions that are caused by parasympathetic nerves: 1) expansion of airways; 2) slowing of heartbeat; 3) constriction of pupils; 4) contraction of bladder.
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What kind of fossil-fuel–based power plant recovers the waste heat that is otherwise lost during conventional thermal power generation, thus achieving effective electric efficiencies of 70% to 90%?
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How do the internal energies compare for dense packings of Janus particles on a cylindrical surface in which each hydrophobic side faces the corresponding hemispheres of all neighbors?
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Two long, straight wires are hanging parallel to each other and are 1 centimeter apart. The current in wire 1 is 5 amperes, and the current in wire 2 is 10 amperes in the same direction. Which of the following BEST describes the magnetic force per unit of length felt on wire 1? W) It is twice the force per unit of length on wire 2 X) It is half the force per unit of length on wire 2 Y) It is 0.001 newtons per meter away from wire 2 Z) It is 0.001 newtons per meter toward wire 2
W: W) It is twice the force per unit of length on wire 2
X: X) It is half the force per unit of length on wire 2
Y: Y) It is 0.001 newtons per meter away from wire 2
Z: Z) It is 0.001 newtons per meter toward wire 2
Answer: Z) Z) It is 0.001 newtons per meter toward wire 2
A 2-kilogram object moves in a circle with a radius of 4 meters at a constant speed of 3 meters per second. A net force of 4.5 newtons acts on the object. What is the angular momentum of the object, in kilogram·meters² per second, with respect to an axis perpendicular to the circle and through its center?
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What is the scientific term for the skeletons of diatoms?
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By number, identify all of the following five characteristics that are TRUE of Humboldt squids: 1) they can reach up to six feet in length; 2) they live about one year on average; 3) they are very passive; 4) they hunt in schools; 5) they can eject themselves from the water into the air to escape predators.
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If sin(2x) = 0.4, then what does (cos x + sin x)² equal?
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Give the interval or intervals of values of x for which the graph of the function f(x) = 5 – x² is above the graph of g(x) = 2x – 3.
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Two solutions are made with equal molarity: one contains sucrose dissolved in water, while the other contains an unknown salt dissolved in water. The freezing point of the sucrose solution is found to be –0.75 °C, and the freezing point of the unknown salt solution is –2.2 °C. Which of the following is the most likely chemical formula of the salt? W) NaCl X) CaCl₂ Y) AlCl₃ Z) AgCl
W: W) NaCl
X: X) CaCl₂
Y: Y) AlCl₃
Z: Z) AgCl
Answer: X) X) CaCl₂
By name or number, identify all of the following five compounds that would be more soluble in carbon tetrachloride than in water: 1) krypton difluoride; 2) sulfur difluoride; 3) sulfur dioxide; 4) carbon dioxide; 5) magnesium fluoride.
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Which of the following was NOT observed at the Tunguska event? W) About eighty million trees were lying on their sides X) Night skies glowed Y) A massive impact crater was formed Z) Energy approximating 2.8 megatons was released
W: W) About eighty million trees were lying on their sides
X: X) Night skies glowed
Y: Y) A massive impact crater was formed
Z: Z) Energy approximating 2.8 megatons was released
Answer: Y) Y) A massive impact crater was formed
By name or number, identify all of the following four bodies of water that are currently experiencing a relative drop in sea level: 1) Mediterranean Sea; 2) Yellow Sea; 3) Hudson Bay; 4) Caribbean Sea.
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Which of the following elements has the lowest freezing point? W) Nitrogen X) Oxygen Y) Sodium Z) Bromine
W: W) Nitrogen
X: X) Oxygen
Y: Y) Sodium
Z: Z) Bromine
Answer: X) X) Oxygen
By name or number, identify all of the following five compounds for which London dispersion is the most significant type of interparticle force present in its solid state: 1) argon; 2) hydrogen chloride; 3) calcium chloride; 4) carbon dioxide; 5) hydrogen sulfide.
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Gap junctions in animal cells and plasmodesmata in plant cells permit which of the following? W) Adjacent cells to adhere strongly to each other X) Secondary messengers produced in one cell to rapidly diffuse into and stimulate events in surrounding cells Y) The passage of connexin signals allowing coordinated cellular responses Z) Rapid exchange of genetic information between adjacent cells
W: W) Adjacent cells to adhere strongly to each other
X: X) Secondary messengers produced in one cell to rapidly diffuse into and stimulate events in surrounding cells
Y: Y) The passage of connexin signals allowing coordinated cellular responses
Z: Z) Rapid exchange of genetic information between adjacent cells
Answer: X) X) Secondary messengers produced in one cell to rapidly diffuse into and stimulate events in surrounding cells
Most insects take in oxygen and expel carbon dioxide through spiracles. What tubes connect directly to the spiracles?
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What type of semiconductor would be formed if a small amount of indium impurity is added to pure selenium?
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By name or number, put the following five compounds in order from lowest to highest melting point: 1) carbon tetrachloride; 2) water; 3) sodium chloride; 4) molecular oxygen; 5) chloroform.
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You find that your maximum error of estimate in determining a population proportion is ±4%, based on your sample size. If you were to repeat the experiment with a sample four times as large, what would your maximum error of estimate be?
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By number, identify all of the following three statements that are TRUE: 1) the area under a normal curve is always equal to one; 2) the larger the standard deviation of a normal curve, the higher and narrower the graph; 3) normal curves with different means are centered around different numbers.
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What is the name of a rotary electrical switch that reverses magnetic field polarity in a DC motor?
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A spring–mass system is vibrating along a frictionless horizontal floor. The spring constant is 8 N/m, the amplitude is 5 cm, and the period is 4 s. What is the mass of the system, in newtons, in terms of π?
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What is the name of the genus for the human itch mite responsible for causing human scabies?
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Relative to their physical size, which two parts of the body have the largest area of the somatosensory map devoted to them?
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What is the name of any material with the same type of crystal structure as calcium titanium oxide and a general chemical formula of ABX₃, where A and B are two cations of very different sizes, and X is an anion that bonds to both?
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Classify the order of each reagent and of the reaction overall between nitric oxide and molecular oxygen to form nitrogen dioxide, given the equation: 2 NO(g) + O₂(g) → 2 NO₂(g) and given that the rate law of this reaction is k [NO]².
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An annular ring with inner and outer radii r₁ and r₂, respectively, is rolling without slipping with a uniform angular speed. What is the ratio of the centripetal forces f₁/f₂ experienced at two points on the inner and outer parts of the ring?
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A 0.5-kilogram book is dropped from a height of 1.5 meters. Given g as 10 m/s², with what kinetic energy, in joules, will it hit the floor? (Give your answer as a decimal to the nearest tenth.)
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What is the name for the lobe-shaped cliffs on Mercury formed by contraction of the crust?
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What type of cloud is formed when warm, moist air runs into the surface of a mountain, ascending on the windward side and descending on the lee side?
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When two tuning forks, fork 1 and fork 2, are sounded simultaneously, 4 beats per second are heard. If the frequency of fork 1 is 200 Hz, then what two values are possible for the frequency of fork 2?
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Two blocks, A and B, of mass 3m and 2m, respectively, are connected by a massless, inextensible string and suspended by a massless spring (A attached to the spring and B hanging below A). The system is initially at rest, then the string connecting the blocks is suddenly cut. Immediately after the string is cut, what are the accelerations of blocks A and B, respectively?
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What is the name of the non-equilibrium state between a solid and a plasma, with potential energy of the interaction between electrons and nuclei roughly of the same magnitude as the kinetic energy of the electrons?
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The cyanobacterium Synechococcus elongatus has a core circadian oscillator that can be reconstituted in vitro from which three purified proteins?
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For a distribution with a mean of 40 and a standard deviation of 8, what is the z-score for a score of 36?
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How many positive integer divisors does 8640 have?
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Which of the following geologic observations would NOT directly assist in the determination of the sequence of geologic events in an area? W) An unconformity between a granite and sandstone X) A well-exposed dike of basalt in sandstone Y) Inclusions of sandstone in a granite pluton Z) The feldspar and quartz contents of a granite
W: W) An unconformity between a granite and sandstone
X: X) A well-exposed dike of basalt in sandstone
Y: Y) Inclusions of sandstone in a granite pluton
Z: Z) The feldspar and quartz contents of a granite
Answer: Z) Z) The feldspar and quartz contents of a granite
What term is used to describe a weather front that is the boundary between two air masses of different moisture content, one of warm, moist air and the other of hot, dry air?
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A moving-coil galvanometer has 150 equal divisions. Its current sensitivity is 10 divisions per milliampere and its voltage sensitivity is 2 divisions per millivolt. In order for each division to read 1 volt, what resistance, in ohms, must be connected in series with the coil? W) 995 X) 9,995 Y) 99,995 Z) 999,995
W: W) 995
X: X) 9,995
Y: Y) 99,995
Z: Z) 999,995
Answer: X) X) 9,995
A pilot flying at 700 m/s experiences an acceleration of 5 g when pulling out of a dive. Given 9.8 m/s² as g, what is the radius, in meters, of curvature of the loop in which the plane is flying?
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Which of the following is NOT a consequence of the apparent stretching of the crust during extension in order to form fault-block mountains? W) Episodes of volcanism X) Doming of the crust Y) Higher heat than average Z) Accretion of terranes
W: W) Episodes of volcanism
X: X) Doming of the crust
Y: Y) Higher heat than average
Z: Z) Accretion of terranes
Answer: Z) Z) Accretion of terranes
Flowville expects significant population growth in the next decade. More people will produce more sewage, and, considering that Flowville Wastewater Treatment Facility only performs primary and secondary treatment, the increased sewage will lead to a higher phosphorus discharge into Flow Lake. As a result of these activities, how will Secchi depth readings at Flow Lake be affected?
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In compact fluorescent light bulbs, conversion of electrical energy into radiant energy occurs due to which of the following? W) Inelastic scattering X) Chemical bonding Y) Phase change Z) Elastic scattering
W: W) Inelastic scattering
X: X) Chemical bonding
Y: Y) Phase change
Z: Z) Elastic scattering
Answer: W) W) Inelastic scattering
Tsunamis are characterized as shallow-water waves. Given g as 10 m/s², which of the following is the approximate velocity, in kilometers per hour, of a tsunami which originates in shallow water, but then propagates in water with a depth of 6100 meters? W) 150 X) 300 Y) 600 Z) 900
W: W) 150
X: X) 300
Y: Y) 600
Z: Z) 900
Answer: Z) Z) 900
Which form of hepatitis is transmitted by ingestion of fecal matter, even in microscopic amounts, and results in an acute but not chronic infection?
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Which of the following insects has a unique muscle arrangement that allows them to power their flight directly? W) Beetle X) Butterfly Y) Dragonfly Z) Cockroach
W: W) Beetle
X: X) Butterfly
Y: Y) Dragonfly
Z: Z) Cockroach
Answer: Y) Y) Dragonfly