I need a quick help to the statistics question in the attachment below

HOMEWORK
1. An economy has grown at 5 percent in the first year, 6 percent in the second year, 4.5
percent in the third year, 3 percent in the fourth year and 7.5 percent in the fifth year.
What is the average rate of growth of the economy during the five years?
2. Suppose we have three observations 4, 8 and 16. We are required to calculate the
harmonic mean. Calculate the harmonic mean of its reciprocal respectively.
3. In a small company, two typists are employed. Typist A types one page in ten
minutes while typist B takes twenty minutes for the same. (i) Both are asked to type
10 pages. What is the average time taken for typing one page? (ii) Both are asked to
type for one hour. What is the average time taken by them for typing one page?