The answer is D. 0.6666666.
Answer:
The probability that a randomly selected component needs rework when it came from line A₁ is 0.3623.
Step-by-step explanation:
The three different assembly lines are: A₁, A₂ and A₃.
Denote <em>R</em> as the event that a component needs rework.
It is given that:

Compute the probability that a randomly selected component needs rework as follows:

Compute the probability that a randomly selected component needs rework when it came from line A₁ as follows:

Thus, the probability that a randomly selected component needs rework when it came from line A₁ is 0.3623.
The answer would be the first choice. 
Explanation: The reason for this is that the question was pretty much just asking what the area of the resulting two-dimensional cross section would be -the shape in gray- (which can be found by using the formula
. To add on, since the dimensions of the shape are already given (5 and 3) all you've to do is multiply: 3*5=15
That's how you get to the answer.
Either B or D I’m not really sure but I know it’s one of this answers