Answer:
- <em>The energy put into a machine or device to make it work is named</em> <u>work input.</u>
Explanation:
<em>Machines </em>are devices to perform tasks with less effort or more easily. They can either increase the force applied or change the direction of the force or permit to apply the force at a distance.
The law of conservation of energy states that the energy is neither created nor destroyed, but when the machines do <em>work</em> some energy is dissipated in the form of heat, light or sound, due, mainly to friction.
In consequence, the <em>work output</em> is less than the <em>work input</em>.
A measure of energy use is efficiency. The efficiency is the ratio of the work output to the work input.

Answer:
DIRECTION
Explanation:
the answer of the blank will be DIRECTION
As the signal is far ahead so driver can make the decision of what he have to do either he can change direction or he can be on his same path.
But for that driver has to change his or her speed.
so, from the statement given the blank will be filled with DIRECTION
Answer: I dont see the option choices
Explanation:
C. The opportunity cost of a student who is staying up all night to study for an exam that he has to take in the early morning is sleep or rest.
<h3>
What is law of opportunity cost?</h3>
The law of increasing opportunity cost is an economic principle that describes how opportunity costs increase as resources are applied.
As the student gives up his sleep or night rest in the place of his exam preparation, we say that the opportunity cost is the sleep or rest.
Thus, the opportunity cost of a student who is staying up all night to study for an exam that he has to take in the early morning is sleep or rest.
Learn more about opportunity cost here: brainly.com/question/8846809
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