Which of the following equations is equal to -x^2-4?

a. (-x-2i) (x+2i)
b. (-x+2i) (x-2i)
-2i) (x-2i)
d. (x+2i) (x-2i)

The weekly amount spent by a company for travel has an approximately normal distribution with mean = $550 and standard deviation = $40. a) what is the probability that the actual weekly expense will exceed $570 for more than 20 weeks during the next year? (note: one year = 52 weeks) b) what is the probability that actual weekly expenses exceed $580 for 10 or more, but 16 or fewer weeks during the next year?