A sociologist is interested in surveying workers in computer-related jobs to estimate the proportion of such workers who have changed jobs within the past year.
a. In the absence of preliminary data, how large a sample must be taken to ensure that a 95% confidence interval will specify the proportion to within ±0.05?
b. In a sample of 100 workers, 20 of them had changed jobs within the past year. Find a 95% confidence interval for the proportion of workers who have changed jobs within the past year.
c. Based on the data in part (b), estimate the sample size needed so that the 95% confidence interval will specify the proportion to within ±0.05.
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a. power grinder b. solvent c. wire brush d. propane torch
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a. food crops are more difficult to grow b. energy crops are more difficult to grow c. most food crops cannot be used to produce energy d. the competition can raise the cost of food
Why is it so difficult to develop for educators a pure “process instrumentation” textbook?
What will be an ideal response?
The subsequent problems deal with the circuit shown below. Assume that the diode is ideal (i.e., has a 0V forward bias voltage).
Using a KVL equation in loop B, which expression below is valid?
A. Vd = ?V2 + I2R2 B. Vd = V2 ? I2R2 C. Vd = V2 ? (I1 + I2)R2 D. Vd = ?V2 ? (I1 ? I2)R2 E. Vd = V2 + I2R2