Please answer all 3 questions with an explanation.

Question#1A

For a certain individual, when they consume one unit of good x1, their utility increases by 10 utils. When they consume a second unit of x1, their utility increases by 7 utils. When they consume a third unit of x1, their utility increases by 5 utils. When they consume a fourth unit of x1, their utility increases by 4 utils. This means that if the individual consumes all 4 units, their total utility is 10+7+5+4=26 utils. Why doesn't each additional unit of x1 provide the same utility as the first unit?The slope of a regression line -0.6 and the standard error of the estimate is 0.15 Based on the following null and alternative hypotheses Ho: b = 0 Ha: b # 0 Calculate the test statistic (the "t-stat").Using your t-stat from the previous question, do you reject the null hypothesis at the 1% level? (In other words, is the coefficient statistically different from 0 at the 1% level?) O Cannot be determined from the information given. O No, do not reject the null hypothesis at the 1% level. Yes, reject the null hypothesis at the 1% level