A publishing house publishes three weekly magazines$--$Daily Life, Agriculture Today, and Stuf's Up$.$ Publication of one issue of each of the magazines requires the following amounts of

production time and paper:

Daily Life

Agriculure Today

Stat's Up

Production $($hr$.)$

$0\mathrm{.}01$

$0\mathrm{.}03$

$0\mathrm{.}02$

Paper $($Ib$.)$

$0\mathrm{.}2$

$0\mathrm{.}5$

$0\mathrm{.}3$

Each week the publisher has available $120$ hours of production time and $3,000$ pounds of paper. Total circulation for all three magazines must exceed $5,000$ issues per week if the company is to keep its advertisers. The selling price per issue is $$2\mathrm{.}25$ for Daily Life, $$4\mathrm{.}00$ for Agriculture To$-$ day, and $$1\mathrm{.}50$ for Swof's Up$.$ Based on past sales, the publisher knows that the maximum weekly demand for Daily Life is $3,000$ issues; for Agriculture Today, $2,000$ issues; and for Surf's Up$,6,000$ issues. The production manager wants to know the number of issues of each maga$-$

zine to produce weekly in order to maximize total sales revenue. The total number of constraints in this problem, including non$-$negativity constraints is: