Problem 1
The portion from t = 0 to t = 5 represents going downhill, which is a total duration of 5 seconds. This is because the speed is going up (the y values are increasing) as you move from right to left for this interval. It looks like you're going uphill here, but keep in mind that the y axis is not position. Instead, the y axis represents speed.
Answer: 5 seconds
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Problem 2
You have the correct table. Nice job. Don't forget to show your work if your teacher requires it.
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Problem 3
f(x) = x*|-2|^x
f(3) = 3*|-2|^3 ... replace every x with 3
f(3) = 3*(2)^3
f(3) = 3*8
f(3) = 24
The input is x = 3 which leads to the output y = 24
The ordered pair (x,y) = (3,24) is on the function curve
Answer: 24