50. as a pendulum swings back and forth,
a) potential energy is transformed into kinetic energy
b) kinetic energy is transformed into potential energy
c) at the lowest part of the swing the potential energy is the lowest
d) all of the above are true

D

Explanation:

the working equation for the angular size is the product of the physical size and 360 degrees divided by the product of two pi and distance from earth. the minimum size would be 0.559 degrees while the maximum size would be 0.49 degrees.