3. About how many carbon-- 14 atoms from a sample of 800 C--14 atoms will remain after
2.0 half-lives? (Show your work)

c. heat from the poles back down towards the equator.

the answer is d p: cell, q: organ, r: organ system, s: tissue

all these collisions do one thing, and that thing is explained in the last option. when dusst, rocks and ice collide, they harden and form giant layers of rocks or hard ice.

d)   to harden materials to form different parts of earth’s layers

hope it ,

bioteacher101