A beam is singly reinforced with the reinforcement in two rows. The bottom row contains 6 No. 6 bars at a depth of 20 in. The top row contains 4 No. 8 bars at a depth of 14 in. Determine the effective (centroidal) depth, d, of the steel.
Read Details(05.01 LC) Samuel, a quality assurance inspector at a donut factory, checks for product quality using a random sample of 7 donuts from a batch of 38, with 14 cake donuts and 24 glazed donuts. Let p̂ be the proportion of cake donuts in the sample. Part A: Is the 10% condition met in this case? Justify your answer. (5 points) Part B: Is the Normal condition met in this case? Justify your answer. (5 points) (10 points)
Read Details(05.05 MC) An ecological group suspects lobsters are consuming dangerous levels of mercury in a region of the world. Dangerous levels of mercury are classified when they reach beyond 6.5 parts per million. A random sample of 25 lobsters in the region were tested and the data is shown in the stemplot. Key: 2|2 = 2.2 parts per million Part A: What proportion of the lobsters in the sample have dangerous levels of mercury in their systems? (4 points)Part B: Construct and interpret a 95% confidence interval for the mean mercury levels of the lobsters if the sample of 25 lobsters has a mean mercury level of 5.05 parts per million and standard deviation of 1.45 parts per million. (6 points)(10 points)
Read DetailsA beam has dimensions of b = 14 in., h = 28 in., d’ = 2.5 in., and d = 25.5 in. It is reinforced with 2 No. 5 bars on the compression side and 5 No. 8 bars on the tension side. The concrete strength is 3,700 psi, and the yield strength of the reinforcement is 60,000 psi. If the depth of the neutral axis is c = 5.588 in., determine the strain in the compression reinforcement, ε’s.
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