Suppose that college faculty with the rank of professor at two-year institutions earn an average of $64,571 per year with a standard deviation of $4,000. In an attempt to verify this salary level, a random sample of 60 professors was selected from a personnel database for all two-year institutions inthe United States and the average salary xwas calculated.

(1)Describe the sampling distribution of the sample mean x

(2)Within what limits would you expect the sample average to lie, with probability 0.95?

(3)If your random sample actually produced a sample mean of $66,000, would you consider this unusual? What conclusion might you draw? Hint: what is the probability of observing a samplemean larger than this?

I've been working on this for a few days and i just don't understand, it's due in a few hours. you. the direction of a vector is defined as the angle of the vector in relation to a horizontal line. as a standard, this angle is measured counterclockwise from the positive x-axis. the direction or angle of v in the diagram is α. part a: how can you use trigonometric ratios to calculate the direction α of a general vector v = < x, y> similar to the diagram? part b suppose that vector v lies in quadrant ii, quadrant iii, or quadrant iv. how can you use trigonometric ratios to calculate the direction (i.e., angle) of the vector in each of these quadrants with respect to the positive x-axis? the angle between the vector and the positive x-axis will be greater than 90 degrees in each case. part c now try a numerical problem. what is the direction of the vector w = < -1, 6 > ?