What’s is the initial value of this function

Autility company burns coal to generate electricity. the cost c(p), (in dollars) of removing p percent of the some stack pollutants is given by c(p)= 85000p/100-p a) find the cost to remove 30% of the pollutant b) find where the function is undefined

For each proportion find the unknown number x 1/5/8=×/15

Write an inequality and solve each problem.for exercises 11 and 12, interpret the solution.