6. I think it's b but I could be wrong hope I helped.
I think is A and the another question is B
Answer:

Step-by-step explanation:
Hope this helps
Kylie's first month collection, a1= $ 145
Second month collection , a2= $145+ 20
Third month collection, a3 = $145 +2*20
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so for n months collection = an-1+20
We get an= 20 + an-1 and a1=145