A dispatch supervisor needs a short midweek report from five teams. One team hasn't reported Tuesday yet, while another reported a genuine zero on Monday. Keep those meanings separate: an average should skip the missing entry but include the zero.
This review mixes the LAMBDA helpers and Apps Script with the reporting habits from earlier levels. Start by deciding the shape of the output. A row total needs one result per team; a running total needs every accumulated result; an overall figure needs only one value. LET can make a repeated calculation easier to read.
The last two tasks use scripts. One returns a range to a cell formula, and one writes a range when you run it. Both must use the current workbook inputs and preserve the requested output shape. Each task starts from a fresh copy, so choose the method from the question rather than from the previous answer.