Modern ventilation and lighting systems have largely eliminated the need for ___ roofs

________ is a fixed false belief

a. Depression b. A delusion c. A hallucination d. A manic-depressive state

Which of the following components are common to a standard compressed gas cylinder manifold system?

1. Automatic switch-over control 2. Pressure-reducing valves 3. Primary and reserve bank 4. Alarm system a. 1, 2, and 3 only b. 2 and 4 only c. 3 and 4 only d. 1, 2, 3, and 4