The predominant gas in the earth's atmosphere is

a.
helium

b.
oxygen

c.
methane

d.
water vapor

e.
nitrogen

Ahill is made of rock particles of different sizes. which of these agents of erosion probably causes the hill to form? a- waves b- glacial ice c- wind d- flowing water

What does this grave marker reveal about roman society

Adesert is an example of a(n) and the gobi desert is an example of a(n) a. ecosystem biome b. biome ecosystem c. ecosystem climate d. climate biome