1. I think you should compare diagrams of moon phases from the textbook to diagrams of moon phases online. Because if you pick D it will take to long and C will help you out whith 3 different things to look at.
2. The moon changes in appearances from the perspective of people on earth because it's revolving around the planet and the earth is revolving around the sun, so A. Hoped this helped.
Answer:
a). A conservative force permits a two-way conversion between kinetic and potential energies.
TRUE
Because there is no energy loss in presence of conservative forces so energy conversion in two ways are possible.
b). A potential energy function can be specified for a conservative force.
TRUE
negative gradient of potential energy is equal to conservative force

c). A non-conservative force permits a two-way conversion between kinetic and potential energies.
FALSE
here energy is lost against non-conservative forces
d). The work done by a conservative force depends on the path taken.
FALSE
work done by conservative force is independent of path
e). The work done by a non-conservative force depends on the path taken.
TRUE
work done by non conservative forces depends on path.
f). A potential energy function can be specified for a non-conservative force.
FALSE
It is not defined for non conservative forces
Answer:
D
Explanation:
As we progress and learn more, scientists make new discoveries that can contradict earlier discoveries, and since are technology is better today we are able to discover a lot more to add to or change our previous theories.