Which of these is not an example of revolving?
A) The process that give us day
and night.
B) The planets moving in orbit
around our star (the Sun).
C) The stars in the galaxy moving
in orbit around the center of
the Milky Way.
D) The process that give us
annual seasons.

A) The process that give us day  and night.

Explanation:

From the answer choices provided the one that is not an example of this is the process that give us day  and night. This is because, the day/night cycle occurs as the Earth spins on it's axis. This cause one side of the Earth to be facing the Sun, which is the side that is currently experiencing day time while the other side is experiencing night time. As the Earth spins the cycles repeat. This is not an example of revolving.

a coal burning power plant

answer: the correct answer is 1.

explanation: there are various process in which a radioactive nuclei decays:

1) alpha decay: in this process, a heavier nuclei decays into lighter nuclei by releasing alpha particle. the mass number is reduced by 4 units.

2) electron capture: in this decay process, a parent nuclei absorbs an electron and gets converted into a neutron. simply, a proton and an electron combines together to form a neutron. mass number does not change in this process.

3) gamma ray emission: it is a decay process in which an unstable nuclei gives excess energy by a spontaneous electromagnetic process. this decay releases . this process does not change the mass number.

4) positron emission: it is a type of decay process, in which a proton gets converted to neutron and an electron neutrino. this is also known as -decay. in this the mass number remains same.

from the above information, we see that only alpha-decay is producing a change in the mass number of the nucleus.