Answer:
Power output = 
Explanation:
Given:
Mass of the elevator is, 
Height to which it is raised is, 
Acceleration due to gravity is, 
Time taken by the motor to raise the elevator is, 
Now, work done on the elevator by the motor is equal to the increase in the gravitational potential energy of the elevator.
Increase in gravitational potential energy is given as:

Therefore, work done by motor is, 
Now, we know that, power is work done in unit time. So, power output is given as:
![Power=\frac{W}{t}\\\\Power=\frac{10\times 10^4\ J}{5.0\ s}\\\\Power=2\times 10^4\ J/s\\\\Power=2\times 10^4\ W..........[1 W = 1\ J/s]](https://tex.z-dn.net/?f=Power%3D%5Cfrac%7BW%7D%7Bt%7D%5C%5C%5C%5CPower%3D%5Cfrac%7B10%5Ctimes%2010%5E4%5C%20J%7D%7B5.0%5C%20s%7D%5C%5C%5C%5CPower%3D2%5Ctimes%2010%5E4%5C%20J%2Fs%5C%5C%5C%5CPower%3D2%5Ctimes%2010%5E4%5C%20W..........%5B1%20W%20%3D%201%5C%20J%2Fs%5D)
Therefore, the power output of the first motor is 
The wavelengths of the constituent travelling waves CANNOT be 400 cm.
The given parameters:
- <em>Length of the string, L = 100 cm</em>
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The wavelengths of the constituent travelling waves is calculated as follows;

for first mode: n = 1

for second mode: n = 2

For the third mode: n = 3

For fourth mode: n = 4

Thus, we can conclude that, the wavelengths of the constituent travelling waves CANNOT be 400 cm.
The complete question is below:
A string of length 100 cm is held fixed at both ends and vibrates in a standing wave pattern. The wavelengths of the constituent travelling waves CANNOT be:
A. 400 cm
B. 200 cm
C. 100 cm
D. 67 cm
E. 50 cm
Learn more about wavelengths of travelling waves here: brainly.com/question/19249186