While there are some very old stars in the halo of our galaxy, the stars that make up the halo are about 50 percent of all the stars in the Milky Way.
O True
O False

Why does physical weathering speed up the processes of chemical weathering? a) physical weathering requires abundant water, as does chemical weathering. b) physical weathering produces fresh surfaces for chemical weathering to attack. c) chemical weathering can occur only on small surfaces, not large ones. d) chemical weathering requires salt, which is provided by salt wedging.

Which process collects sample soils from particular areas of a site? a.) repetitive sampling b.) restorative sampling c.) random sampling d.) representative sampling

If x ≤ 25, which could be the perimeter of this rectangle? a) 100 in b) 155 in c) 225 in d) 750 in e) 1500 in