Need halp solving this practice problem. thanks for your help in advance !

a. Fill in the data for MTD, STD and YTD for each month. The first receipt of this item was July...vour company uses the 4-5-4 calendar b. Which month from part A (July, August or Sept) had the best performance? Explain. c. How many units would you need to sell in the month of October to have a 17% sell-thru for the month of October (with no additional units received)