d. (5n-9)
Step-by-step explanation:
First term = -4Common difference = 1-(-4)=1+4=5Formula used: L =a+(n-1)d
where, L is the last term;
a is the first term ;
n is the number of terms;
and d is the common difference.
L = -4+(n-1)5= -4+5n-5 = 5n-9
Therefore, the last term is (5n-9).