I was stuck on the same thing in my class test. I ended up failing but if I get the answers to it I’ll totally send them to you!!!
I'm pretty sure it would be y=2x+9
1300 = 1000 (1.08)^t
1.3 = (1.08)^t
log base 1.08 (1.3) = t
3.41 = t
I think it should be 6.5 inch but I'm not positive.
I hope this helps! :))