A recent study focused on high-speed internet cost (in dollars) for households in a certain population. Monthly high-speed internet bills for 36 randomly selected households from the population were obtained. The researcher plans to use the results to estimate the population mean monthly high-speed internet cost for all households in this population.

The researcher remembers that the data should first be examined graphically and produced the following 00 plot. Nomal Q-Q Plot for Monthly Internet Cost cu ia' n ' > To E z c 'D a 13 a) '- n- I it cu 40 45 50 55 60 Observed Value State the assumption that this graph is used to assess (in context). Consider a different population of households and suppose it is known that for this population the mean monthly high-speed internet cost is $50 and the population standard deviation is $6. Suppose we are planning to take a random sample of 36 households from this population and will be computing the smaple mean monthly high-speed internet cost for these 36 households. Which of the following graphs provides the approximate model for the possible values of the sample mean monthly cost? Graph A Graph B Graph C density density density 32 38 44 50 56 62 68 47 48 49 50 51 52 53 44 46 48 50 52 54 56 O Graph A O Graph B O Graph C