D
Because the rest of the answers are illogical
Higher voltage means faster rotation. Changing the voltage polarity changes the direction of the motor.
The independent variable refers to the type of socks (synthetic socks), the dependent variable is the number of blisters and the control is the two weeks that she switches back to the cotton socks.
<h3>What is the dependent variable?</h3>
In an experiment, the dependent variable is those being tested and changes according to the independent variable.
The control group is the set of experimental conditions that is used to compare a given outcome in an experiment.
In conclusion, The independent variable refers to the type of socks (synthetic socks), the dependent variable is the number of blisters and the control is the two weeks that she switches back to the cotton socks.
Learn more about the dependent variable here:
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Answer:

Explanation:
14 lb force is required to stretch the spring by 4 inch distance
So we have



stretch in the spring is given as

now we will have



Now we need to find the work to stretch it by x = 10 in = 0.254 m
so we have



The 5kg object 5m/s 1 m off the ground