The marketing group for a software development company plans to conduct a telephone survey to determine

customer attitudes towards new potential products under development. In order to have a sufficient sample size to

conduct the analysis, they need to complete surveys with at least $200$ respondents from each demographic group

$($young male, older male, young female, older female$).$ It costs $$2\mathrm{.}00$ to make a week day $-$ daytime survey call and

$$2\mathrm{.}50$ to make an evening or weekend phone call. This cost is incurred whether or not anyone answers the phone.

Table $1$ shows the probability of a given customer type answering the phone during each time window. Assume the

survey is conducted with whoever first answers the phone. In order to level load the staffing requirements, no more

than $42\%$ of the calls can be made during any one time window. How should the marketing group conduct the

telephone survey so as to meet the sample size requirements at the lowest possible cost? $($solve in excel using solver$)$