Based on current evidence, when is/was liquid water abundant on the surface of Mars?
A) only before about 3 billion years ago
B) only during the first 1 million years of Mars's existence
C) Water comes and goes, with the most recent water flows occurring a few thousand years ago.
D) only during the most recent 1 billion years of Mars's history
A) only before about 3 billion years ago
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How did Mars get its two moons? a. Mars captured asteroids from the asteroid belt
b. Mars suffered a catastrophic meteor impact, breaking a piece off the planet. c. Mars had planetary bodies near it when the solar wind blew out the nebula. d. Mars collided and fused with another planet leaving two remnants behind. e. Mars captured comets from the Kuiper belt.
Which of these statements about Hubble's classification scheme for galaxies is false?
A) It represents an evolutionary sequence for galaxies (e.g., type SBa galaxies slowly turn into type SBb). B) Sc galaxies have smaller bulges and more dusty gas than Sa galaxies. C) It includes two broad types of spiral galaxies. D) Low numbered elliptical galaxies are rounder than high numbered elliptical galaxies.
Which of the following is true about Neptune?
a) Its atmospheric composition and rings are most like Saturn's. b) Its atmospheric composition is most like Saturn's, but its rings aremore like thoseof Uranus and Jupiter. c) Its atmospheric composition is most like Uranus and its rings are likethose of Uranusand Jupiter. d) Its atmospheric composition and its rings are most like Jupiter's. e) It is more like the Earth than it is like any of the other giant planets.
In projectile motion the vertical component of the velocity at the top of the trajectory is
A. non-zero, and less than the initial vertical component of the velocity. B. non-zero, and equal to the initial vertical component of the velocity C. zero D. non-zero, and greater than the initial vertical component of the velocity