1. scientists can use rock layers to determine which of the following?
a. the mass of earth
b. the size of earth
c. the age of earth
d. the amount of land on earth

2. fossils in layers of rock are generally estimated to be than fossils found in the deeper layers.
a. older, younger
b. newer, younger
c. older, older
d. newer, older

3. new evidence can lead to a change in scientific knowledge
true or false