The heart's top and bottom chambers are separated by valves that prevent backflow of blood

The ____ lay is used where the fire and the water source are in two different directions, such as on two different streets.

A. forward B. split C. reverse D. modified

All unresponsive trauma patients should be assumed to have which of the following?

A. Intoxication B. Spinal injury C. Low blood sugar D. High blood sugar