Use the exponential distribution below to answer Questions #21 - 28. Extensive experience with fans of a certain type used in diesel engines has suggested that the exponential distribution with A =...

Extracted text: Use the exponential distribution below to answer Questions #21 - 28. Extensive experience with fans of a certain type used in diesel engines has suggested that the exponential distribution with A = 15,000 provides a good model for time until failure (in hours). Find the variance. Round to four decimal places as needed.


Extracted text: Use the exponential distribution below to answer Questions #21 - 28. Extensive experience with fans of a certain type used in diesel engines has suggested that the exponential distribution with A = 15,000 provides a good model for time until failure (in hours). Find the standard deviation. Round to four decimal places as needed.