ANSWERING THE FOLLOWING IN R STUDIO

#1)A study was made by a retail merchant to determine the relationship between #weekly advertising expenditures and sales. The following data were recorded: ad.cost <- c(40, 20, 25, 20, 30, 50, 40, 20, 50, 40, 25, 50) sales <- c(385, 400, 395, 365, 475, 440, 490, 420, 560, 525, 480, 510)

#a) Plot a scatter plot

#b) Find the 90% interval of the range of the mean of sales when #ad expenditures is $35 (About $430.089 to $482.779)

#c) Determine the 90% interval of the potential range of values for the sales #when the ad expenditures is $35 (from about 361.666 to 551.202)

#d) Determine the 90% interval of the potential range of values for the sales #when the ad expenditures is $40 (from about 376.887 to 568.189)

#2) The amount of chemical compound (labeled grams), which dissolved in 100 #grams of water at various temperatures (labeled temp) were recorded as #follows: temp <- c(0, 0, 0, 15, 15, 15, 30, 30, 30, 45, 45, 45, 60, 60, 60, 75, 75, 75) grams <- c(8, 6, 8, 12, 10, 14, 25, 21, 24, 31, 33, 28, 44, 39, 42, 48, 51, 44)

#a)Find the equation of the regression line.

#b) Plot the scatter plot and draw the line on the graph

#c)Estimate the average Chemical that will dissolve in 100 grams of water at 50 #degrees. (about 34.225)

#d) What is the 75% interval range for the average grams when temp is 20? (correct #answer is about 16.301 to 18.054)

#e)What is the 75% interval for the value when temp is 45? (correct answer is #between 28.206 and 34.530)