Write a formula for the general term [the nth term] of each arithmetic Sequence. Do not use a recursion formula. Then use the formula for an to find aq the 20th term of the Sequence. an =an-1- 1D,a1 = 312] A. an=-1Dn;a=-2o B. an= FD- 1Gn;a=-5D C. an=4- 1Dn; a=-1 D; an = 10- 1Dn;a=-?D