Answer:
The sun's energy comes from thermonuclear fusion reactions.
Explanation:
Due to the Sun's strong gravitational pull, hydrogen atoms fuse, resulting in helium atoms. During this process, tremendous amounts of energy are released, or the energy of the Sun.
Answer:

Explanation:
The torque applied by a force can be calculated as

where
F is the magnitude of the force
d is the length of the arm
is the angle between the direction of the force and the arm
In this problem, we have
F = 15 N
d = 2.0 m

Substituting into the equation, we find

Answer:
increasing; speeding up is my answer
Sound wave > electric signal > radio wave > sound wave