Question

could anyone help me!!!!
1. a dartboard consists of two concentric circles. the probability of hitting the inner circle is 64% if the outer circle has a diameter of 20 inches what is the radius of the inner circle?
A. 2 inches
B. 4 inches
C. 8 inches
D. 16 inches
2. using a sixteen-sided number cube what is the probability that you will roll an even number or an odd prime number? the number 1 isnt an odd prime. round to the three decimals
A. 0.063
B. 0.813
C. 0.219
D. 0.156