Chemical cleaning operation, involving using chemical solvent with (specific gravity = 1.5, Molecular weight = 129). During the process, (75.7 liter) of the solvent evaporates during each working shift that includes 8 working hours. The process take place at room temperature; and pressure maintained at 1 atm. Assume ventilation rate equal 1,000 ft^3/min. a. Determine evaporation rate in lbm/min

b. Determine the concentration in ppm assuming poor mixing (NOT the worst case scenario: Not extremely poor mixing)

c. If the PEL for the solvent is 100 ppm, based on your previous calculation explain weather the workers are allowed to do the job or not. Provide explanation.

d. Assume worst-case scenario (extremely poor mixing) and the PEL to be 100 ppm calculate the required ventilation rate and comment on your obtained answer.