I Dont understand formulas and its frustrating trying to forecast monthly sales and growth

One mistake that I notice: the formula in E12 is =(($T$12*365)/12)+(1-E4).
It should be =(($T$12*365)/12)*(1+E4).

Similarly in E13.

Example: if you start with $100 and you want 10% more, you would write 100*(1+10%), which is $110.

Another mistake: the formula in F12 is =E12*F4+$E$12.
Close! But it should be =E12*F4+E12 so that it can be replicated down and across.
Alternatively, you could write =E12*(1+F4), similar to E12.

Finally, the formula in F14 is =$E$6*(F6). Although it produces the correct result (0) by coincidence, technically it is incorrect because there is no information in E6 and F6 related to category C.

That's all I noticed on first glance. I really have not looked at the assignment in any detail.

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