I want answer to the following question?

How can we draw simple diagram of what is happening with circular buffering?

In case the DSP board is unable to finish the calculations before the next sample arrives, briefly discuss (in point form) how the following measures could help solve that issue: lowering the sampling frequency, using a lower order filter, and using Circular Buffered FIR Filtering (Memory Pointers) instead of Brute-Force FIR Filtering (i.e., rotating the coefficients physically.

how changing the order of the low-pass MA Filter will affect the cutoff frequency

what is frequency domain representation of the MATLAB MA Filter of order 4 and 32