Please help Which condition will calls particles to diffuse faster across a membrane

A: an increase in size of the particles
B: The same amount of particles on each side
C: Cooling of the temperature
D: A steep concentration gradient

Describe at least two advantages and two disadvantages of using hydropower as a source of energy.

Harry lives in a city, and he has a lung condition known as asthma. on certain days, harry has to stay inside because pollutants in the air make it difficult for him to breathe. which of these pollution sources are nonpoint sources that might bother harry if he goes outside? choose the two that apply.

The independent variable in an experiment will be the variable that you o a) change ob) hold constant ng c) observe for changes