Jupiter and saturn each have the same three basic cloud layers, but the spacing of the layers differs on the two planets. why is this?
a. on saturn, the "rain" of helium condensate has forced the lower layers downward, so they are more separated there.
b. jupiter's greater gravity has compressed the layers, so they are closer together there.
c. jupiter's greater rotation rate has flung the layers outward, so they are separated more there.
d. jupiter's warmer temperature has expanded the atmosphere, so they are more separated there.

b. Jupiter’s greater gravity has compressed the layers, so they are closer together there.

Explanation:

The value for Jupiter mass is 1.8981×10²⁷kg, while the mass of Saturn is 5.6832×10²⁶kg, so the different layers of clouds in Jupiter will be submitted to a greater gravitational pull because it has a bigger mass, as is established in the law of universal gravitation:

  (1)

Where m1 and m2 are the masses of two objects, G is the gravitational constant and r is the distance between the two objects.

As it can be seen in equation 1, the gravitational force is directly proportional to the product of the masses of the objects, so if the mass increase the gravitational force will do it too.  

For the case of Saturn, it has a lower mass so its layers of clouds will suffer a weaker gravitational pull. That leads to the three clouds being more spacing that the ones of Jupiter.    

current and voltage can both be different in different parts of a circuit so it matters where you place the ammeter and voltmete