Entropy can only be decreased in a system if
a)heat is removed
b)disorder is increased
c)energy is added
d)efficiency is zero
answer fast

a)heat is removed

Explanation:

Entropy is the a stare of randomness or disorderliness of the particles of a system.

The entropic level of a system depends on temperature and physical state of matter.

With increasing temperature, the randomness of the particles of a system increases. When heat is removed from a system, the entropy reduces and orderliness is approached. For example, the entropy of steam would decrease if we place it in a refrigerator. In the refrigerator, work is done on the steam to remove the heat and reduce the temperature. The vapour moves from gas to liquid and then to a more ordered ice.

When disorder increases, entropy increases also.

When we add more energy to a system, it causes a rise in randomness.

explanation:

as the height from which the ruler was dropped increased, the speed of the ruler at ryan's hand increased.