The answer is B, The speed is constant and the velocity is changing.
As we know that here no air resistance while ball is moving in air
So here we will say that
initial total energy = final total energy

here we know that
(as it will be on ground at initial and final position)
so we will say

since mass is always conserved
so we will say that final speed of the ball must be equal to the initial speed of the ball
so we have

Principle: Pythagorean theorem
Given:
Let a = boat velocity = 25 miles per hour
b = river velocity = 10 miles per hour
Required: c = actual velocity
Solution:
c^2 = a^2 + b^2
c^2 = (25)^2 + (10)^2
c^2 = 725
(c^2)^0.5 = (725)^0.5
c = 26.93 miles per hour
<em>ANSWER: Actual boat velocity is 26.93 miles per hour</em>
Explanation:
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