Final answer:
To find P(A and B), multiply P(A|B) by P(B). The result is 0.10.
Step-by-step explanation:
To find P(A and B), we can use the formula P(A and B) = P(A|B) × P(B). Since it is given that P(A|B) = 0.5 and P(B) = 0.20, we can substitute these values into the formula to get P(A and B) = 0.5 × 0.20 = 0.10.
Therefore, the correct answer is a) 0.10.