Why did the following change occur ? the snow that covered the ground all winter began to melt, temperature rose, and flowers started to bloom.
a) days became shorter b) earth's tilt on its axis shifted. c) the sun's rays became more concentrated d) earth completed one revolution

Amountain created from tectonic activity would be considered which type of landform ? a) primary landform b) secondary landform

Which factors add to the greenhouse effect and are caused by human activities?

If we represent the solar system on a scale that allows us to walk from the sun to pluto in a few minutes, then a) the planets are microscopic and the stars are millions of miles away. b) the planets are the size of basketballs and the nearest stars are a few miles away. c) the planets are marble size or smaller and the nearest stars are thousands of miles away.