18. Eyeglassomatic manufactures eyeglasses for different retailers. In March 2010, they tested to see how many defective lenses they made, and there were 16.9% defective lenses due to scratches. Suppose Eyeglassomatic examined twenty eyeglasses.

a.) State the random variable.

b.) Argue that this is a binomial experiment Find the probability that

c.) None are scratched.

d.) All are scratched.

e.) At least three are scratched.

f.) At most five are scratched.

g.) At least ten are scratched.

h.) Is it unusual for ten lenses to be scratched? If it turns out that ten lenses out of twenty are scratched, what might that tell you about the manufacturing process?