I'm sorry for asking a petty question. But, I think here is the best place to ask.
If we have a polynomial $a(x)$ of degree $k-1$
$a(x) = \sum_{i=0}^{k-1}a_i x^i$
I know we can say that the degree of $a(x)$ is $k-1$ since degree refers to the highest number of exponents.
Can we say that the number of exponents is $k$?