N= (Round up to the nearest integer)
2) An environmental agency worries that many cars may be violating clean air emissions standards. The agency hopes to check a sample of vehicles in order to estimate that percentage with a margin of error of 4% and 95% confidence. To gauge the size of the problem, the agency first picks 50 cars and finds 11 with faulty emissions systems. How many should be samples for a full investigation?
The agency should sample at least ___ vehicles. (Round up to nearest whole number)
3) The electric current (In A) in a circuit with a battery of voltage E, a resistance R, and an inductance L, is i= E/R(1-e^-Rt/L), where t is the time after the circuit closed. Find I expressed in milliamps (mA) for E= 6.40,V, R=1.20 Q, L=3.26 H, and t=0.001 s.
I= ____ mA
4) A biotechnology firm is planning its investment strategy for future products and research labs. A apoll found that 6% of a random sample of 1037 adults approved of attempts to clone a human. Use this information to complete parts a through e.
a) Find the margin of error for this poll if we want 95% confidence in our estimate of the percent of adults who approve of cloning humans. ME=
5) Direct mail advertisers send solicitations (junk mail) to thousands of potential customers in the hope that some will buy the company’s product. The response rate is usually quite low. Suppose a company wants to test the response to a new flyer and sends it to 1200 people randomly selected from their mailing list of over 200,000 people. They get orders from 135 of the recipients
Create a 90% confidence interval for the percentage of people the company contacts who may buy something. (___%,___%). (Round to one decimal place as needed..
Theeff
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