need helb with b and c

The last four years of returns for a stock are as shown here a. What is the average annual return? b. What is the variance of the stock's returns? c. What is the standard deviation of the stock's returns? Note: Notice that the average return and standard deviation must be entered in percentage format. The variance must be entered in decimal format. a. What is the average annual return? The average return is 990% (Round to two decimal places) Data table 1 X (Click on the following icon in order to copy its contents into a spreadsheet.) Year 1 2 3 Return 43% +27.89 + 118% +43% Print Done