5, 8, 11, ... is an arithmetic sequence where:

I'm not sure if this is right. I didn't feel confident with my answer.
Answer:
fg(-2)=f(5×-2+4)=f(-6)=8-10×-6=8+60=68

=3
r=common ratio: 12/6=2; 6/3=2
r=2,

=

*3
plug in 12 for n:

=
*3

=

*3

=2048*3

=6144
The twelfth term in the sequence is 6144
Pretty sure it’s B. Hope this helps :)