(05.05 MC) An ecological group suspects dolphins are consum…
(05.05 MC) An ecological group suspects dolphins are consuming dangerous levels of arsenic in a region of the world. Dangerous levels of arsenic are classified when they reach beyond 7.0 parts per million. A random sample of 28 dolphins in the region were tested and the data is shown in the stemplot. Key: 2|4 = 2.4 parts per million Part A: What proportion of the dolphins in the sample have dangerous levels of arsenic in their systems? (4 points)Part B: Construct and interpret a 99% confidence interval for the mean arsenic levels of the dolphins if the sample of 28 dolphins has a mean arsenic level of 5.26 parts per million and standard deviation of 1.49 parts per million. (6 points)(10 points)
Read DetailsThe elastic beam theory is not used in the design of reinfor…
The elastic beam theory is not used in the design of reinforced concrete beams because (1) the compressive stress-strain relationship for concrete becomes non-linear at higher strain values and (2) concrete cracks at low tensile stresses making it necessary to use reinforcing steel.
Read DetailsA beam has dimensions of b = 18 in., h = 30 in., and d = 27….
A beam has dimensions of b = 18 in., h = 30 in., and d = 27.5 in. and is reinforced with 5 No. 7 bars. The concrete strength is 10,000 psi, and the yield strength of the reinforcement is 60,000 psi. Assuming the reinforcement has yielded, determine the depth to the neutral axis, c.
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