Please give me answers I'm slow in the head

On the april 3 billing date, michaelle chappell had a balance due of $ 1495.39 on her credit card. from april 3 through may 2, michaelle charged an additional $ 305.34 and made a payment of $ 800.a) find the finance charge on may 3, using the previous balance method. assume that the interest rate is 1.8 % per month.b) find the new balance on may 3.

Which value is not a solution of 8x^3 – 1 = 0

I’m really confused and need your assist me with this question i’ve never been taught