Why do clouds look gray when there is a storm?

Why does physical weathering speed up the processes of chemical weathering? a) physical weathering requires abundant water, as does chemical weathering. b) physical weathering produces fresh surfaces for chemical weathering to attack. c) chemical weathering can occur only on small surfaces, not large ones. d) chemical weathering requires salt, which is provided by salt wedging.

What are the answers for the following questions?

Good scientists always report their observations and results truthfully. this is especially important when a scientist's results go against previous ideas or predictions. coming up with inventive ways to solve problems or produce new things