Answer:
0.3721 or 37.21%
Step-by-step explanation:
P(I) = 0.60; P(II) = 0.40;
P(not defective I) = 0.90; P(not defective II) = 0.80
The probability that the phone came from factory II, given that is not defective, is determined by the probability of a phone from factory II not being defective divided by the probability of a phone not being defective.

The probability is 0.3721 or 37.21%.
You can use the properties of exponents in three ways: Products of Power and Power to Power
Explanation:
Product of a Power: When you multiply exponentials with the same base, you add their exponents
Power to a Power: When you have a power to a power, you multiply the exponents.
Quotient of Powers: When you divide exponentials with the same base, you subtract the exponents.
Intersect with x axis indicates that x value would be Zero
Thus when x = 0
y would be
y = -18
Therefor intersection would be at (0,-18)