HS Sample Set 12, Round 17 from NSB
Which of the following ocean currents does NOT flow from higher latitudes toward the equator? W) The California Current X) The Peru Current Y) The Brazil Current Z) The Benguela Current
W: W) The California Current
X: X) The Peru Current
Y: Y) The Brazil Current
Z: Z) The Benguela Current
Answer: Y) Y) The Brazil Current
Which of the following events occurred in the Late Mississippian? W) Breakup of Rodinia X) Collision of Gondwana with Laurasia Y) Collision of Laurentia with Baltica Z) Breakup of Pangaea
W: W) Breakup of Rodinia
X: X) Collision of Gondwana with Laurasia
Y: Y) Collision of Laurentia with Baltica
Z: Z) Breakup of Pangaea
Answer: X) X) Collision of Gondwana with Laurasia
What are the x-coordinates of the intersections of the graphs of the equations $$y = 9x^2 + 3$$ and $$y = -27x + 3$$?
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What is the cube of the complex number $$3 + 5i$$?
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A student wishes to convert an aldehyde to a secondary alcohol. Which of the following reagents would be most useful? W) Alkyl Grignard reagent X) Lithium aluminum hydride Y) Sodium borohydride Z) Sodium hydride
W: W) Alkyl Grignard reagent
X: X) Lithium aluminum hydride
Y: Y) Sodium borohydride
Z: Z) Sodium hydride
Answer: W) W) Alkyl Grignard reagent
Identify all of the following three names that unambiguously represent the structure of a benzene ring with an alcohol group in the 1-position and a primary amine in the 4-position: 1) P-aminophenol; 2) 4-aminophenol; 3) 4-hydroxyaniline.
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Planck resolved the ultraviolet catastrophe for black bodies by postulating the quantization of photon energies to derive an expression showing that the modal energies obey which of the following statistical distributions? W) Fermi-Dirac X) Maxwell-Boltzmann Y) Bose-Einstein Z) Gaussian
W: W) Fermi-Dirac
X: X) Maxwell-Boltzmann
Y: Y) Bose-Einstein
Z: Z) Gaussian
Answer: Y) Y) Bose-Einstein
A spinning dancer draws her arms inwards until she rotates at 3 times her original velocity. In terms of her original kinetic energy $$E$$, how much energy did this maneuver require?
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Identify all of the following four phyla that exhibit radial symmetry: 1) Porifera; 2) Cnidaria; 3) Mollusca; 4) Echinodermata.
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In humans, circadian rhythms are controlled by a specific group of neurons in the hypothalamus called what?
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Scientists at Lawrence Berkeley National Lab recently captured images of a Type one-A supernova in a galaxy four billion light-years away that appeared 50 times brighter than normal and in four different places in the sky. Which of the following did the scientists discover? W) A Type-one-A supernova with a progenitor that was 20-50 times more massive than normal X) An anomalous type-two supernova with a light curve resembling type Ia Y) A light echo of a type-one-A supernova Z) A type-one-A supernova whose image was strongly gravitationally lensed
W: W) A Type-one-A supernova with a progenitor that was 20-50 times more massive than normal
X: X) An anomalous type-two supernova with a light curve resembling type Ia
Y: Y) A light echo of a type-one-A supernova
Z: Z) A type-one-A supernova whose image was strongly gravitationally lensed
Answer: Z) Z) A type-one-A supernova whose image was strongly gravitationally lensed
One of the most promising generation IV nuclear reactor designs involves the use of supercritical water as the coolant. What is the main reason to use supercritical water? W) It has a higher neutron absorption cross section X) It has a lower neutron absorption cross section Y) It is fissile Z) It allows for a higher thermal efficiency
W: W) It has a higher neutron absorption cross section
X: X) It has a lower neutron absorption cross section
Y: Y) It is fissile
Z: Z) It allows for a higher thermal efficiency
Answer: Z) Z) It allows for a higher thermal efficiency
Which of the following drainage patterns would likely be visible on jointed, rocky terrain? W) Dendritic X) Trellis Y) Radial Z) Rectangular
W: W) Dendritic
X: X) Trellis
Y: Y) Radial
Z: Z) Rectangular
Answer: Z) Z) Rectangular
Identify all of the following three latitudes that trade winds can be found in: 1) Between 60° and 30° south; 2) Between 30° south and the equator; 3) Between the equator and 30° north.
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A patient is demonstrating loss in bone density. Which of the following hormones would be most useful in treating this symptom? W) Parathyroid hormone X) Vasopressin Y) Calcitonin Z) Mineralocorticoid
W: W) Parathyroid hormone
X: X) Vasopressin
Y: Y) Calcitonin
Z: Z) Mineralocorticoid
Answer: Y) Y) Calcitonin
Identify all of the following three statements that are true of nitrogenous waste excretion: 1) Ammonia excretion results in more water loss than an equivalent amount of urea excretion; 2) Urea is more energetically expensive to excrete than an equivalent amount of uric acid; 3) Humans produce a small amount of uric acid.
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DOE scientists are using the Advanced Light Source to study atmospheric reentry heat shields, including PICA, the type currently used by NASA and SpaceX. Which of the following best describes PICA? W) A silicone-based heating pad X) A highly-thermally-conductive epoxy Y) A carbon fiber that slowly ablates Z) Titanium shingles with heat sinks
W: W) A silicone-based heating pad
X: X) A highly-thermally-conductive epoxy
Y: Y) A carbon fiber that slowly ablates
Z: Z) Titanium shingles with heat sinks
Answer: Y) Y) A carbon fiber that slowly ablates
Scientists at SLAC recently demonstrated that coating the gold tip of an electron gun with nanodiamonds resulted in a higher electron flux through the gun. This is because the diamonds changed what property of the electron gun tip? W) Conductance X) Electron density Y) Voltage Z) Work function
W: W) Conductance
X: X) Electron density
Y: Y) Voltage
Z: Z) Work function
Answer: Z) Z) Work function
What is the product of the three different prime factors of 315?
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What is the approximation for the sine of 2 that results from using the first three nonzero terms of the Taylor series for $$\sin x$$ centered at 0?
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In terms of the elementary charge $$e$$, what is the electric charge of an up quark?
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An excess charge is distributed over the surface of a solid metal sphere that has a radius of one meter. Identify all of the following three distances from the center of the sphere at which the electrical potential relative to infinity is maximized: 1) 50 cm; 2) 100 cm; 3) 150 cm.
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The precipitation reaction caused by the addition of potassium chloride to aqueous silver nitrate is an example of which of the following types of reactions? W) Metathesis X) Decomposition Y) Synthesis Z) Redox
W: W) Metathesis
X: X) Decomposition
Y: Y) Synthesis
Z: Z) Redox
Answer: W) W) Metathesis
Copper (II) hydroxide is insoluble in water. However, upon the addition of excess ammonia, it dissolves and changes to a deep blue color. Which of the following statements best explains this observation? W) The rise in pH solubilized the copper hydroxide X) The drop in pH solubilized the copper hydroxide Y) The copper reacted with ammonia, forming a soluble species Z) The ammonia neutralized the hydroxide, releasing soluble copper (II)
W: W) The rise in pH solubilized the copper hydroxide
X: X) The drop in pH solubilized the copper hydroxide
Y: Y) The copper reacted with ammonia, forming a soluble species
Z: Z) The ammonia neutralized the hydroxide, releasing soluble copper (II)
Answer: Y) Y) The copper reacted with ammonia, forming a soluble species
The five-prime cap added to mRNA is a modified version of what nucleotide base?
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Identify all of the following three statements that are true regarding a neuron at rest: 1) Voltage-gated sodium channels are mostly open; 2) Voltage-gated potassium channels are mostly open; 3) The sodium-potassium pump is hydrolyzing ATP.
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When looking at it through a plane mirror, a flagpole appears to be 10 cm tall. Given that the eye-to-mirror distance is 0.4 m and the total eye-to-mirror-to-pole distance is 30 m, what is the actual height of the flagpole, in meters?
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A cannon fires several cannonballs at the same initial speed but at several different angles, the furthest landing 100 m away. What is the slowest possible speed, in meters per second and to the nearest ten, at which these cannonballs could have been fired?
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Lithium-ion batteries are generally built in the discharged state, then recharged after construction. Which of the following best explains why this is done? W) The materials in the discharged state can be exposed to the atmosphere safely X) In the charged state, the raw materials pose a risk of dendrite formation Y) Lithium dendrites cannot form in the discharged state Z) Lithiated manganese materials are particularly unstable in the presence of humidity
W: W) The materials in the discharged state can be exposed to the atmosphere safely
X: X) In the charged state, the raw materials pose a risk of dendrite formation
Y: Y) Lithium dendrites cannot form in the discharged state
Z: Z) Lithiated manganese materials are particularly unstable in the presence of humidity
Answer: W) W) The materials in the discharged state can be exposed to the atmosphere safely
Identify all of the following three statements that are true concerning their findings on the El Niño Southern Oscillation (ENSO): 1) El Niño is accompanied by increased likelihood of rainfall over California; 2) The intensity of ENSO events will likely increase due to climate change; 3) The variability in yearly rainfall will likely increase globally due to ENSO events.
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Which of the following substances is more soluble in toluene than in water? W) Carbon tetrachloride X) Sodium chloride Y) Acetic acid Z) Sodium methoxide
W: W) Carbon tetrachloride
X: X) Sodium chloride
Y: Y) Acetic acid
Z: Z) Sodium methoxide
Answer: W) W) Carbon tetrachloride
A physical chemist has determined the vapor pressure of a liquid at multiple temperatures and wants to determine the standard entropy of vaporization. Which of the following sets of axes will enable the chemist to graph the data as a line and determine the entropy from the y-intercept? W) Pressure on y, temperature on x X) One over pressure on y, temperature on x Y) Natural log of pressure on y, temperature on x Z) Natural log of pressure on y, one over temperature on x
W: W) Pressure on y, temperature on x
X: X) One over pressure on y, temperature on x
Y: Y) Natural log of pressure on y, temperature on x
Z: Z) Natural log of pressure on y, one over temperature on x
Answer: Z) Z) Natural log of pressure on y, one over temperature on x
What is $$\displaystyle \int_{9}^{64}\frac{d}{dx}\sqrt{x}\,dx\;?$$
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The graph of the polar equation $$r = 6\cos\theta$$ is a circle. What are its radius and Cartesian-coordinate center, respectively?
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A soil sample is extracted from a soil monolith in a temperate forest environment. The sample contains a relatively high concentration of sand and silt as well as leached minerals. What soil horizon does the sample represent? W) A X) B Y) C Z) E
W: W) A
X: X) B
Y: Y) C
Z: Z) E
Answer: Z) Z) E
What is the name for a location on Earth that does not have tides?
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What quantity, inversely related to compressibility, measures a material’s ability to resist pressures coming from all sides, such as when underwater?
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Identify all of the following three quantities that are dimensionless: 1) Tensile stress; 2) Tensile strain; 3) Young’s Modulus.
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How many terms does the binomial expansion of $$(8x^3 + 5y^2)^{18}$$ contain?
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What are the coordinates of the image of the point $$(-1, 4)$$ when it is rotated about the point $$(3, 2)$$ by 90 degrees counterclockwise?
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What is the name of the jelly-like fluid that fills the human eye?
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Identify all of the following three vitamins that are considered fat-soluble: 1) Biotin; 2) Cobalamin; 3) Niacin.
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Identify all of the following three statements that are true regarding the denticity of ligands: 1) Bromine is a monodentate ligand; 2) Diethylenetriamine is a bidentate ligand; 3) EDTA is a quadradentate ligand.
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Identify all of the following three molecules that have the chemical formula C₄H₈O: 1) Acetone; 2) Butanone; 3) Butyraldehyde.
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What spectral class of stars possesses the strongest Balmer lines?
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When muons are created by cosmic rays at 99.5% of the speed of light, their lifetime as observed on Earth is extended by time dilation. Given that their rest lifetime is approximately 2.2 microseconds, what is their observed lifetime, to two significant figures and in microseconds?
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