Which of the following are commonly shown on a geologic map ?

a. rock ages
b. hachure lines
c. index contours
d. scale and legend

In the water cycle , when does water undergo a chemical change

In which of the following relationships is one organism always benefited while the other organism is always harmed

The embryos of a bird, a reptile, and a mammal are similar in appearance. how does comparing the physical appearance of embryos of different species support the theory of evolution? a. it shows that these organisms share a common ancestor. b. it provides evidence that these organisms eat the same foods.c. it shows that these organisms share the same habitat.d. it provides evidence that these organisms suffered a genetic mutation.