Which radioisotope requires long-term storage as the method of disposal, to protect living things from radiation exposure over time? A) Pu-239 B) Fr-220 C) Fe-53 D) P-32

What is impossible to do with a hypothesis

Why do scientists look for patterns in the world? a. patterns can explain observations. b. patterns never change, no matter what. c. patterns are easy for scientists to detect. d. patterns are all the same, through all time.

How did planetesmals form planets? a. they broke apart into smaller chunks.b. they collided and stuck together.c. they cooled and pulled ice together.d. they began to rotate.