The question is:
f(x)=
show that (f·)(a)=a=(·f)(a) for any a in the respective domains.

can somebody explain the question to me? i'm not even sure what it means. what are respective domains? ?

Jude is making cement for a driveway. the instructions show the amount of each ingredient to make 1 batch of cement. complete each statement to adjust the ingredients for each new situation if jude uses these instructions.