Solve each problem.

Indoor Air Pollution Formaldehyde is an indoor air pollutant formerly found in plywood, foam insulation, and carpeting. When concentrations in the air reach 33 micro grams per cubic foot (μg/ft³), eye irritation can occur. One square foot of new plywood could emit 140 mg per hr.

(a) A room has 100 ft² of new plywood flooring. Find a linear equation F that computes the amount of formaldehyde, in micrograms, emitted in x hours.

(b) The room contains 800 ft³ of air and has no ventilation. Determine how long it would take for concentrations to reach 33 μg/ft³. (Round to the nearest tenth.)