Answer:
he maximum frequency occurs when the denominator is minimum
f’= f₀ 
Explanation:
This is a doppler effect exercise, where the sound source is moving
f = fo
when the source moves towards the observer
f ’=f_o
Alexandrian source of the observer
the maximum frequency occurs when the denominator is minimum, for both it is the point of maximum approach of the two objects
f’= f₀ 
<span>They are balanced. If the forces were not balanced the book would move*. In this example, the downward force of gravity on the book is counterbalanced by the upthrust of the desk. </span>
I'm giving you a general formula , its called ohm law it states that <span>electric current is proportional to voltage and inversely proportional to resistance
if V=voltage associated with the battery
R=resistance , I=current then
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Answer:
49 kg is the mass of the couch.
Explanation:
GPE = mgh
9800 = m * 10 * 20
9800 = 200m
m = (9800/20) = 49 m
Thenks and mark me brainliest :))