1. Which type of radiation has direct influence on the greenhouse effect?
A) Microwave
B) Alpha
C) Gamma
D) Infrared
2. In a chemical laboratory the total ventilation air flow rate is 3000 CFM. Permissible concentration (by EPA)of the chemical that can leave the exhaust system into the atmosphere is 50 ppm. Concentration level at the worker's breathing zone is 200 ppm and the PEL is 400 ppm.Assuming a Safety factor of 5, calculate the rate of recirculated air in CFM. Show all your calculations.(No credit will be given if you do not include your calculations)
3. The isotopes of an element have the same atomic mass number.
True
False