Answer:
The probability of founding exactly one defective item in the sample is P=0.275.
The mean and variance of defective components in the sample are:

Step-by-step explanation:
In the case we have a lot with 3 defectives components, the proportion of defectives is:

a) The number of defectives components in the 5-components sample will follow a binomial distribution B(5,0.075).
The probability of having one defective in the sample is:

b) The mean and variance of defective components in the sample is:

The Chebyschev's inequality established:

H(t) = 0 for t = 7 and for t = -2.
It is reasonable for the time to be positive, 7 seconds.
(The offered answers all appear to be negative, so none are reasonable.)
Step-by-step explanation:
The slop is M= 1÷x-y-xy
12%... (3×4)/(25×4) = 12/100... 12/100 = .12 which is 12%