Write a Formula for the General Term (The Nth Term)of $r a _ { n }$

Multiple Choice

Write a formula for the general term (the nth term) of the arithmetic sequence. Then use the formula for $r a _ { n }$ to find $a _ { 20 }$ , the 20th term of the sequence.
- $$a _ { n } = a _ { n - 1 } + 10 , a _ { 1 } = 18$$

A) $a _ { n } = 10 n + 8 , a _ { 20 } = 208$
B) $a _ { n } = 18 n - 8 , a _ { 20 } = 352$
C) $a _ { n } = 10 n + 28 , a _ { 20 } = 228$
D) $a _ { n } = 8 n + 10 , a _ { 20 } = 170$