Answer:
A
Explanation:
It varies from person to person.
I think we will use the law of conservation of linear momentum;
M1V1 = M2V2
M1 = 4 kg (mass of the water balloon launcher)
V1=?
M2= 0.5 kg ( mass of the balloon)
V2 = 3 m/s
Therefore; 4 V1 = 0.5 × 3
4V1= 1.5
V1= 1.5/4
= 0.375 m/s
The correct choice is
D. 22 Hz and 42 Hz.
In fact, the beat frequency is given by the difference between the frequencies of the two waves:

In this problem, the beat frequency is
, therefore the only pair of frequencies that gives a difference equal to 20 Hz is
D. 22 Hz and 42 Hz.
2m/s
Explanation:
Given parameters:
Distance traveled = 60m
time taken = 30seconds
Unknown:
Speed of skateboarder = ?
Solution:
Speed is the rate of change of distance with time taken. It is a scalar quantity that only revers magnitude;
Speed = 
Speed =
= 2m/s
learn more:
Speed brainly.com/question/1548911
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