An Engineer Wants to Know If the Average Amount of Energy

question 59

Essay

An engineer wants to know if the average amount of energy used in his factory per day has changed since last year. The factory used an average of 2,000 megawatt hours (mwh) per day prior to last year. Since last year, the engineer surveyed 400 days and found the average energy use was 2,040 mwh per day. Assume that the population standard deviation is 425 mwh per day.
A) Specify the null and alternative hypotheses to determine whether the factory's energy use has changed.
B) Calculate the value of the test statistic and the p-value.
C) At the 5% significance level, can you conclude that the energy usage has changed? Explain.

• A) Specify the null and alternative hypotheses to determine whether the factory's energy use has changed.
• B) Calculate the value of the test statistic and the p-value.
• C) At the 5% significance level, can you conclude that the energy usage has changed? Explain.

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Definitions:

Retentive Timer

A type of PLC timer that retains its value even after the power is turned off or the controlling logic is no longer true.

Nonretentive Timer

A timer in a control system that does not retain its count or state after a power cycle, restarting from zero.

Retentive

In the context of programmable logic controllers, refers to memory or functions that retain their value or state even after the PLC is turned off or loses power.

Loss Of Power

Loss of power refers to the interruption or cessation of electrical supply to a system, device, or facility, affecting its operation and functionality.