1.An array of thirty LED bulbs is used in an automotive light. The probability that a bulb is defective is 0.001 and defective bulbs occur independently. The expected number of automotive lights to check to obtain a light with two or more defective bulbs is closest to:

2.Suppose that a healthcare provider selects twenty patients randomly (without replacement) from among five hundred to evaluate adherence to a medication schedule. Suppose that ten percent of the five hundred patients fail to adhere with the schedule. The probability that fewer than ten percent of the patients in the sample fail to adhere with the schedule is closest to:

3.The number of failures of a testing instrument from contamination particles on the product is a Poisson random variable with a mean of 0.02 failures per hour. The probability of at least one failure in a twenty-four hour day is closest to:

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4.The rise time of a reactor is measured in minutes (and fractions of minutes). Let the sample space be positive, real numbers. Define the events A and B as follows: A={x|x<72.5} and B={x|x>52.5}. Which of the choices below represents AB:

5.A bin of 50 parts contains 5 that are defective. A sample of 10 parts is selected at random, without replacement. The number of samples that contain at least four defective parts is closest to: