Amachine is supplied energy at a rate of 4,000 w and does useful work at a rate of 3,760 w. what's the efficiency of the machine? a. 92 percent b. 97 percent c. 96 percent d. 94 percent

The efficiency is (d).94%

Step-by-step explanation:

The efficiency:

E=100× (output/input)

So the input is 4000W and the out put is 3760W

From the above formula

E=100×(3760/4000)

E=376000/4000

E=94%

answer: hence, function will be

explanation:

since we have given that

cost of a new textbook = $85

according to question, the resale value of a textbook decreases by 25% with each previous owner,

so, our function becomes,

here, y is the total value of the text book after x owners.

hence, function will be

the correct answer would be d because the slope is -2/2=1 and the y intercept is at 2 so that is the correction equation