Find the first, fourth, and tenth terms of the arithmetic sequence described by the given rule. a(n)=1+(n-1)(5.7)

To find first term, you need substitute
n=1
a(n)=1+(n-1)(5.7)
a(1)= 1+(1-1)(5.7)=1
a(1) =1

Fourth term,
n=4
a(4)=1+(4-1)(5.7)
a(4) = 18.1

For 10th term,
n=10
a(10)=1+(10-1)(5.7)=52.3