Question 18.what causes clouds to reflect a portion of sunlight back to space

The correct option is d.

Explanation:

Albedo is defined as the fraction of total incident solar radiation reflected by a planet back to space. It is the fraction of light reflected by the surface.

It is a measure of the planet's energy balance. The value of albedo is dependent on the spectrum of incident radiation.

Therefore, a characteristic known as albedo causes clouds to reflect a portion of sunlight back to space.

0.93xc=0.93x3x10^8m/s

2.54cm is 1 inch

360seconds i 1 hr

one "light year" is the distance that light travels, through vacuum, in one julian year.   that's 365.25 days, of 24 hours each.