Answer:
at the highest point of the path the acceleration of ball is same as acceleration due to gravity
Explanation:
At the highest point of the path of the ball the speed of the ball becomes zero as the acceleration due to gravity will decelerate the motion of ball due to which the speed of ball will keep on decreasing and finally it comes to rest
So here we will say that at the highest point of the path the speed of the ball comes to zero
now by the force diagram we can say that net force on the ball due to gravity is given by

now the acceleration of ball is given as


so at the highest point of the path the acceleration of ball is same as acceleration due to gravity
Answer:
147.45 Hz

Explanation:
v = Speed of sound in water = 1482 m/s
= Speed of whale = 4.95 m/s
The difference in frequency is given by

Frequency of the wave in stationary condition

Ship's frequency which is reflected back




The difference in wavelength is 147.45 Hz
A body accelerates due to net force acting on it. As newton's second law of motion states:
when a net force acts on a body, it produces acceleration in the body in the direction of the net force
The awnser is. 1728000 kilometers
Remark
You have to pick a velocity for an ultra sound wave. I'm going to take the sound velocity to be 331 m/s in air, because I'm assuming that is what is meant: it is the sound a bat would make once he emits the ultrasound to a microphone like device that receives it. The media through which that happens is air.
Givens
v = 331m/s
f = 4 *10^4 hz
Formula
velocity = wavelength * frequency
v =
*f
331/(4*10^4) = 
0.008275 = 
8.275*10^-3 = 