Prior to first use.
Weekly, and prior to first use.
Daily, or when changing test water.
Monthly, or when changing test water.
The same source of supply used by the host airfield
A liquid is far less compressible than a gas.
A gas is far less compressible than a liquid.
A liquid is more combustible than a gas.
A gas is more combustible than a liquid.
They mix well together.
One liquid will float on the other.
They will become an intrained solution.
They will repel each other and react violently.
Feet per second
Gallons per minute.
Cubic feet per second.
Cubic gallons per minute.
Friction, applied forces, and gravity.
Friction, inertia, and atmospheric pressure.
Gravity, atmospheric pressure, and inertia.
Gravity, atmospheric pressure, and applied forces.
The size of the pipe.
The specific gravity of the fuel.
The change in gallons per minute.
The amount of extinguished velocity.
Pounds per square inch.
Protons, neutrons, and electrons.
Neutrons, elements, and protons.
Electrons, molecules, and elements.
Electrons, neutrons, and matter.
Protons have positive charges, and electrons have neutral charges.
Protons have neutral charges, and electrons have positive charges.
Protons have negative charges, and electrons have positive charges.
Protons have positive charges, and electrons have negative charges.
The outermost shell.
The middle shell.
The second shell.
The first shell.
An atom that lost a proton and has more electrons.
An atom that lost an electron and has more protons.
An atom that has an equal number of electrons and protons.
An atom that cannot throw off any protons.