Radioactive elements can be used for dating rocks because the decay rate of radioactive elements
A.)is not affected by the environment
B.)is linked to Earth's motion
C.)can be controlled by scientists
D.)can increase with time

In a classic experiment using pea shape, mendel conducted two separate genetic crosses. in the first cross the parent plants were “true breeding” for pea shape; one had round peas ( r )and the other had wrinkled (r). the first cross produced a filial 1 generation of all round peas. in the second cross, mendel bred plants from the filial 1 generation. this cross produced different results. out of approximately 1000 plants, about 75% were round and 25% were wrinkled.

Ascientific idea becomes valid when it is what?

Which describes the changes in the earths motion?