HS Sample Set 12, Round 9 from NSB
Which of the following is NOT true? W) 37 is congruent to 6 mod 5 X) 71 is congruent to 5 mod 3 Y) 43 is congruent to 8 mod 7 Z) 17 is congruent to 2 mod 3
W: W) 37 is congruent to 6 mod 5
X: X) 71 is congruent to 5 mod 3
Y: Y) 43 is congruent to 8 mod 7
Z: Z) 17 is congruent to 2 mod 3
Answer: W) W) 37 is congruent to 6 mod 5
Find the y-intercept of the line passing through the point (4, –3) that is perpendicular to the line 3x – 7y = 12.
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At the National Renewable Energy Lab, scientists are using sunlight to split what chemical compound during photoelectrochemical processes that employ stacks of light-absorbing semiconductors immersed in an acid-water solution? W) Methane X) Ammonia Y) Hydrogen Peroxide Z) Water
W: W) Methane
X: X) Ammonia
Y: Y) Hydrogen Peroxide
Z: Z) Water
Answer: Z) Z) Water
Identify all of the following three statements that are true of secondary batteries: 1) They are not rechargeable 2) They require a constant source of energy 3) The electricity-producing reaction in them is chemically reversible
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Addition of which of the following compounds will increase the solubility of calcium carbonate in water? W) Sodium carbonate X) Phosphoric acid Y) Sodium hydroxide Z) Calcium chloride
W: W) Sodium carbonate
X: X) Phosphoric acid
Y: Y) Sodium hydroxide
Z: Z) Calcium chloride
Answer: X) X) Phosphoric acid
What term, which can be applied to all carbon-carbon bond interactions in the compound cyclohexane, refers to a conformer in which vicinal groups are separated by a 60-degree torsion angle?
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Which of the following numbers corresponds to the approximate temperature in kelvins of red stars? W) 300 X) 3,000 Y) 30,000 Z) 300,000
W: W) 300
X: X) 3,000
Y: Y) 30,000
Z: Z) 300,000
Answer: X) X) 3,000
Identify all of the following three statements that correctly characterize annular eclipses: 1) They occur during the waxing gibbous phase of the lunar cycle 2) They occur when the moon is at apogee 3) They are a type of lunar eclipse
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Cataracts occur in what part of the eye? W) Retina X) Posterior chamber Y) Cornea Z) Lens
W: W) Retina
X: X) Posterior chamber
Y: Y) Cornea
Z: Z) Lens
Answer: Z) Z) Lens
What is the only full human chromosomal monosomy that results in viable offspring?
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The henry is the SI unit corresponding to what property of an electric circuit?
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An object in uniform circular motion has its centripetal acceleration halved while its radius remains constant. By what factor is its rotational period multiplied?
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If the total energy flux from a star quadruples, by what factor is its temperature multiplied? W) √2 X) 2 Y) 4 Z) 16
W: W) √2
X: X) 2
Y: Y) 4
Z: Z) 16
Answer: W) W) √2
You are observing a distant star with an orbiting planet whose orbital plane is perfectly oriented so you can observe the exoplanet’s transit in front of the star. In which of the following orientations will the star-planet system appear brightest? W) When the planet is directly in front of the star X) When the planet is directly behind the star Y) Just after the planet transits in front of the star Z) Just before the planet transits behind the star
W: W) When the planet is directly in front of the star
X: X) When the planet is directly behind the star
Y: Y) Just after the planet transits in front of the star
Z: Z) Just before the planet transits behind the star
Answer: Z) Z) Just before the planet transits behind the star
Fungal cell walls are primarily composed of what compound?
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In what compartment of the ruminant stomach does fermentation primarily occur? W) Rumen X) Reticulum Y) Omasum Z) Abomasum
W: W) Rumen
X: X) Reticulum
Y: Y) Omasum
Z: Z) Abomasum
Answer: W) W) Rumen
The pKa of deprotonation for most primary amines is between 35 and 45. Which of the following is closest to the pKa of cyanamide, a primary amine in which the R group is a cyano group? W) 1 X) 15 Y) 35 Z) 45
W: W) 1
X: X) 15
Y: Y) 35
Z: Z) 45
Answer: W) W) 1
Some compounds feature two-atom covalent bonds in which both electrons forming the bond are donated by one of the atoms, also known as a dative bond. Which of the following bonds is most likely to be a dative bond? W) Carbon-carbon X) Sodium-fluorine Y) Nitrogen-boron Z) Hydrogen-chlorine
W: W) Carbon-carbon
X: X) Sodium-fluorine
Y: Y) Nitrogen-boron
Z: Z) Hydrogen-chlorine
Answer: Y) Y) Nitrogen-boron
According to the Standard Model of Particle Physics, what lepton is the most massive?
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A particle undergoing a constant acceleration starts at rest at position x = 0. Identify all of the following three pairs of positions it could be at after one second and then after two seconds, respectively: 1) x = 0, then x = 0 2) x = 3, then x = 12 3) x = 2, then x = 16
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A bag contains six uniquely marked marbles. One marble is drawn, and then a second, without replacement. How many different permutations are possible?
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A right triangle has hypotenuse of length 59 and one leg of length 57. What is the length of the third side?
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In order to better design materials that can tolerate the extreme pressures and temperatures of controlled fusion reactions, researchers at LANL are simulating the behavior of bubbles of what gas embedded in tungsten?
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Which of the following best describes the discharge curve of a Leclanché cell when graphing output voltage versus time? W) An initial rise, then a line with zero slope X) An initial dip, then a line with zero slope Y) A line with positive slope Z) A line with negative slope
W: W) An initial rise, then a line with zero slope
X: X) An initial dip, then a line with zero slope
Y: Y) A line with positive slope
Z: Z) A line with negative slope
Answer: Z) Z) A line with negative slope
What is the systematic name of propyl iodide?
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Identify all of the following three molecules that have a net dipole moment: 1) Silicon tetrachloride 2) Chloroform 3) Hydrogen sulfide
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What is the equivalent resistance, in ohms, of a circuit composed of a 2-ohm resistor connected in parallel to a series branch with two 3-ohm resistors?
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Two electrons are held close together and then released. Identify all of the following three statements that are true regarding this system: 1) Acceleration increases as time passes 2) Velocity increases as time passes 3) Force between the electrons decreases as time passes
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Which of the following minerals would scratch all of the others? W) Quartz X) Calcite Y) Halite Z) Topaz
W: W) Quartz
X: X) Calcite
Y: Y) Halite
Z: Z) Topaz
Answer: Z) Z) Topaz
Which of the following rock types is thought to originate in the deep mantle and is an economically important source of diamonds? W) Kimberlite X) Diabase Y) Anorthosite Z) Amphibolite
W: W) Kimberlite
X: X) Diabase
Y: Y) Anorthosite
Z: Z) Amphibolite
Answer: W) W) Kimberlite
The U.S. Department of Energy's Thomas Jefferson National Accelerator Facility is studying the components of protons and mesons. The quarks inside these particles are held together by interactions mediated by what boson?
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One of the experiments at Brookhaven National Lab, PHENIX, is attempting to measure the temperature of quark-gluon plasma. Which of the following is closest to the known lower limit of this temperature? W) The temperature of the Sun's chromosphere X) The temperature of the Sun's core Y) 2500 times the temperature of the Sun's core Z) 250,000 times the temperature of the Sun's core
W: W) The temperature of the Sun's chromosphere
X: X) The temperature of the Sun's core
Y: Y) 2500 times the temperature of the Sun's core
Z: Z) 250,000 times the temperature of the Sun's core
Answer: Z) Z) 250,000 times the temperature of the Sun's core
In humans, what gland makes melatonin?
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Which of the following processes does not change allele frequencies in a population? W) Genetic drift X) Natural selection Y) Inbreeding Z) Gene flow
W: W) Genetic drift
X: X) Natural selection
Y: Y) Inbreeding
Z: Z) Gene flow
Answer: Y) Y) Inbreeding
What type of organized, low-pressure weather system is an intermediate stage between a tropical depression and a hurricane?
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What is the average plate velocity, to the nearest whole centimeter per year, of a volcanic island that has moved 2500 kilometers away from its parent hot spot in 28 million years?
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Given f(x) = 4x – 6 and g(x) = 3x, what is g(f(x))?
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What is the sum of the first 12 terms of the arithmetic sequence whose first two terms are 5 and 9, respectively?
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Unpolarized light with an intensity of I passes through a filter that makes a 50-degree angle with respect to the horizontal. In terms of I, what is the intensity of the light after it passes through the filter?
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A particle is moving along an axis so that its potential energy is decreasing from point A to B, at a critical point at point B, increasing from point B to D, at a critical point at point D, and decreasing after that. Identify all of the following three statements that are true regarding this particle: 1) Point A is a stable equilibrium 2) Point B is an unstable equilibrium 3) Point D is a stable equilibrium
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Hans Bethe is famous for the development of what theory of coordination in which metal-ligand interactions are assumed to be completely ionic?
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A student constructs a ball and stick model of a linear molecule. Identify all of the following statements that could be valid for this molecule: 1) The central atom has zero lone pairs 2) The central atom has two lone pairs 3) The central atom has three lone pairs
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What reflex describes the profound decrease in heart rate of marine mammals upon feeling cold water on the face?
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Identify all of the following three amino acids that are considered nonpolar: 1) Asparagine 2) Tryptophan 3) Glutamine
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The complex number 3i lies on the boundary between what two quadrants in the complex plane?
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On a calculus pop quiz, 10% of the students scored 6 points, 45% scored 8 points, 20% scored 9 points, and the rest scored 10 points. What is the average score, rounded to the nearest tenth, on the quiz?
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