Atennis ball machine serves a ball vertically into the air from a height of 2 feet, with an initial speed of 130 feet per second. after how many seconds does the ball attain its maximum height?

We use the equation of motion,

.

Here, v is final velocity, u is initial velocity and a = - g (acceleration due to gravity) because ball thrown vertically into air.

At maximum height, the final velocity becomes zero, i.e v = 0.

Thus equation becomes,

 .

Given, and we take  .

Substituting these values in above equation, we get

.

Thus, to reach the maximum height the time taken by the ball is 4.05 s.

a high pressure system is a dense air mass that is usually cooler and drier than the surrounding air. a low pressure system is a less dense air mass that is usually wetter and warmer than the surrounding air.

in general, areas that experience high atmospheric pressure also experience fair weather. low pressure systems can cause the formation of clouds and storms. air usually flows from areas of high pressure to areas of low pressure..

i think the answer is a, hope this is right, that would be my best guess.