Suppose A and B are events with P(A)=1/6, P(B)=5/6 and P(A and B)=1/12. Find each of the following

Question

a. P(AorB)=
Formula: P(A)+P(B)-P(A&B)
1/6+5/6-1/12=11/12
b. P(not A)
1-1/6=5/6
c.P(not B)=
1-1/12=11/12
I am lost here can please correct any mistakes I did with my calculation and please show me the steps.Thank You.