Ou are a graduate assistant for a statistics class where there have been two exams so far. 89 students took the first exam, and the class had an average score of 69.1 with a standard deviation of 12.3 across the students’ scores. 74 students took the second exam, and the class had an average score of 64.35 with a standard deviation of 9.47 across the students’ scores. the professor wants to know if the average scores on the two exams are significantly different, and he asks you to perform a hypothesis test at the 0.05 significance level.

Alarge tank is filled to capacity with 500 gallons of pure water. brine containing 2 pounds of salt per gallon is pumped into the tank at a rate of 5 gal/min. the well-mixed solution is pumped out at the same rate. find the number a(t) of pounds of salt in the tank at time t.

Martha is one producer in the perfectly competitive jelly industry. last year, martha and all of her competitors found themselves earning economic profits. if there is free entry and exit, what do you expect to happen to the number of suppliers in the industry and the price of jelly? the number of suppliers will increase, and the price of jelly will fall. the number of suppliers will decrease, and the price of jelly will increase. the number of suppliers will increase, and the price of jelly will increase. the number of suppliers will decrease, and the price of jelly will fall.

What do u want to be when u grow up