The standard deviation of the lifespan of a certain brand of LED light bulbs is 23 months. The quality control department at this company takes a random sample of 75 LED light bulbs and finds the mean lifespan of sample is 135 months. What is the probability that this sample mean is within 1 months of the mean of all light bulbs produced by the company

Zahra was given two data sets, one without an outlier and one with an outlier. data without an outlier: 15, 19, 22, 26, 29 data with an outlier: 15, 19, 22, 26, 29, 81

Acable company wants to provide cell phone service for residents on an island. the function for the cost of laying the cable from the island to the mainland is c(x)= 6.500 square root x2+4, where x represents the length of the cable in feet. what are the domain and range of the function? a) domain: all real numbers range: all real numbers greater than or equal to 17,000 b) domain: all real numbers greater than or equal to 0 range: all real numbers greater than or equal to 17,000 c) domain: all real numbers greater than or equal to 0 range: all real numbers greater than or equal to 13,000 d) domain: all real numbers greater than or equal to 13,000 range: all real numbers greater than or equal to 0

How much is $1200 worth at the end of1 year, if the interest rate is 5.5% is compounded quarterly.