I need help with question 26 mostly! And there is a follow-up question I am stuck on asking:

Use information in Q24. Measure the error accuracy of July and August using the mean squared error (MSE).You may round up final results. Hint: actual and forecast of July are given, use the forecast of August that you have found in question 26, find the square errors for July and August, then sum them up and divide by 1)

Please help ! I am very stuck

Table below includes time series information including actual demand values of June, July and August. Forecast the demand of September using three- period moving average.{use this table to answer questions 24 to 27} Month Actual Demand in units Forecast in units Weight June 120 July 125 122 25% August 118 75% September O 122.5 units 0 121 units O 121.5 units O 118 units QUESTION 25 Forecast September demand using weighted moving average (use Table information provided in Question 24). You may round up the final result digits.) hint: Do Not consider June as it has no weight O 118 units 120 units 0 121 units O None of above QUESTION 26 Forecast September demand using Exponential Smoothing with a smoothing constant of 90% .{use information in Question 24}. you may round up final result digits. Hint: the forecast and actual values for July are given so you should find August forecast first (=122+0.9*(125-122), then, do the same to find September forecast (2 steps worth 2 points) O 117 units O 119 units O 125 units O 122 units