The results of a recent World Health Organization (WHO) study stated that a 90% confidence interval on the annual cost of rabies in Asia and Africa was $540 - $626 (in millions). Use these numbers to answer the following questions. Show how you got your answer for each, and write the answer as a sentence.
a. What is the WHO's point estimate of the annual cost of rabies in Asia and Africa?
b. What is the margin of error?
c. What is the width of the interval?