The vast flood deposits prove Mars once had much running water. What happened to it?
What will be an ideal response?
As Martian volcanism died down, the atmosphere became too thin for greenhouse gases to keep the water liquid. Most froze in the polar caps or as tundra underground, and some was also lost into space, like Venus lost its due to exposure to ultraviolet light.
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Power: For the graph shown in the figure, what physical quantity does the slope of the graph represent for a dc circuit?
A. 1/(resistance) B. resistance C. potential D. (potential)2 E. 1/(potential)
An incompressible fluid is flowing through a pipe with a constriction. The pipe is on an incline with an angle of 30.0 degrees. The narrow section is 10.0 m from the wide section and the narrow section is higher than the wide section. The velocity of the fluid in the wide section of the pipe is 4.00 m/s and the velocity of the fluid in the narrow section of pipe is 9.00 m/s. The pressure of the fluid in the wide section is 250 kPa. What is the pressure in the narrow section of the pipe? (density of the fluid is 1000 
A. 169 kPa B. 175 kPa C. 180 kPa D. 193 kPa E. 205 kPa
Elementary particles that experience the weak nuclear force but not the strong nuclear force are called
A) hadrons. B) baryons. C) leptons. D) mesons. E) bosons.
Thin Films: A 360-nm thick oil film floats on the surface of a pool of water water. The indices of refraction of the oil and the water are 1.5 and 1.33, respectively. When the surface of the oil is illuminated from above at normal incidence with white light, what are the two wavelengths of light between 400 nm to 800 nm wavelength that are most strongly reflected?
A. 410 nm and 700 nm B. 430 nm and 720 nm C. 450 nm and 740 nm D. 470 nm and 760 nm E. 490 nm and 780 nm