The linear correlation between violent crime rate and percentage of the population that has a cell phone is minus−0.918 for years since 1995. do you believe that increasing the percentage of the population that has a cell phone will decrease the violent crimerate? what might be a lurking variable between percentage of the population with a cell phone and violent crime rate?
will increasing the percentage of the population that has a cell phone decrease the violent crime rate? choose the best option below.

a. no
b. yes
what might be a lurking variable between percentage of the population with a cell phone and violent crime rate?

a. overall cell phone signal strength
b. the police
c. the economy
d. the average cell phone's effectiveness as a weapon

Acaterer knows he will need 60, 50, 80, 40 and 50 dinner napkins on five successive evenings. he can purchase new napkins initially at 25 cents each, after which he can have dirty napkins laundered by a fast one-day laundry service (i.e., dirty napkins given at the end of the day will be ready for use the following day) at 15 cents each, or by a slow two-day service at 8 cents each or both. the caterer wants to know how many napkins he should purchase initially and how many dirty napkins should be laundered by fast and slow service on each of the days in order to minimize his total costs. formulate the caterer’s problem as a linear program as follows (you must state any assumptions you make): a. define all variables clearly. how many are there? b. write out the constraints that must be satisfied, briefly explaining each. (do not simplify.) write out the objective function to be minimized. (do not simplify.)