Which statement about gravity is true?
a. it depends on other forces like frictiont to work.
b. it is described as a fundamental force and therefore does not depend on other forces.
c. it depends on velocity.

When someone eats food

The correct option is this: the sound waves from the two trombones have slightly different frequencies.from the question given above, we are told that the loudness of the sounds were increasing and decreasing, this is because the frequencies of the two sounds are different. the means that the number of waves that pass a fixed point in a given amount of time differ for both sounds.

20,000 should be the answer