Answer:
C
Explanation:
If you have more than one variable then you wont know which variable caused the change. Hope this helped, if it did give it a thanks or whatever.
Answer:Silicon
Explanation: It would be considerably difficult to build computers with a gas.
The barnacles are only able to attach them selfs to surfaces in the water. Since the surface is limited, barnacles are attaching themselves to the other barnacles, crowding the rock. The muscles were not able to grow or attach themselves off the surface of the rock. Same thing with the mussels that are growing on the rock. So not only barnacles are crowding the rock, but Mussels as well are crowding the rock.
The grass affects the movement by helping the water not over flow / flood
