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.
- $2,6,10,14,18 , \ldots$

A) $a _ { n } = 4 n - 2 ; a _ { 20 } = 78$
B) $a _ { n } = 2 n - 4 ; a _ { 20 } = 36$
C) $a _ { n } = 4 n + 2 ; a _ { 20 } = 82$
D) $a _ { n } = n + 4 ; a _ { 20 } = 24$