I really need help on this question In 1-2 complete sentences, summarize how the frequency of a wave is measured.
thank you if you were able to help :)

Wave frequency can be measured by counting the number of crests (high points) of waves that pass the fixed point in 1 second or some other time period. The higher the number is, the greater the frequency of the waves. The SI unit for wave frequency is the hertz ( Hz ), where 1 hertz equals 1 wave passing a fixed point in 1 second.

Explanation:

here we know that ball will drop down by total distance 3.2 m

so here we know that

now using kinematics

now in the same time it will cover horizontal distance of 0.75 m

so speed of the ball will be

total distance/total time

(85 + 82)/(5+3)

167/8

20 just over