If the sum of an arithmetic sequence is 476, the last term is 20, and the number of terms is 17, what is the first term?A32B34C36D38Answer: C. 36Read Explanation:Sn=n/2(T1+Tn) 476=17/2(T1+20) 476×2/17 =T1+20 56=T1+20 T1=36Open explanation in App