From past experience, a professor knows that the test scores of a student taking the final exam is a random variable with mean 75 and the variance is 16. How many students would have to take the exam to ensure with probability 0.9 that the class average would be within 5 of 75

State whether weight is a function of height for the six students and explain. a. yes, height is a function of weight because two students weigh 165 pounds but have different heights. b. no, height is not a function of weight because two students weigh 165 pounds but have different heights. c. yes, weight is a function of height because for each value of height there is one corresponding value of weight. d. no, weight is not a function of height because there is not enough data to determine a function.

The function a represents the cost of manufacturing product a, in hundreds of dollars, and the function b represents the cost of manufacturing product b, in hundreds of dollars. a(t) = 5t + 2 b(t) = 7t - 2t +4 find the expression that describes the total cost of manufacturing both products, a(t) + b(t). a. 7t^2 - 7t + 2 b. 7t^2 + 3 +6 c. 7t^2 + 7t - 6 d. 7t^2 - 3t + 6

Does the point (1, sqrt 7) lie on circle shown.