When is the muting circuit operative?

A. A fixed high pressure cylinder.

B. A high pressure portable cylinder.

C. A fixed cylinder with masks and a breathing hood system.

A. When the parking brake is applied.

B. During 5 minutes after the second engine is shut down.

C. When CVR TEST pushbutton is pressed.

A. By setting the landing gear lever to the "UP" position.

B. By shock absorber extension.

C. By auto brake deactivation.

A. The ram air inlet flaps of the air conditioning packs open

B. The ram air outlet flaps of the air conditioning packs open

C. The emergency ram air inlet flap opens

A. To ensure self centering of the nose gear.

B. To adjust the nose wheel steering speed.

C. To adjust the rate of depressurization in the hydraulic block.

A. The cut-out and vent valves operate .

B. The safety and cut-out valves operate .

C. The safety and vent valves operate .

A. The Ground Power Control Unit has tripped the external ground cart.

B. The external ground cart is connected to the aircraft network.

C. The external ground cart can be connected to the aircraft network.

A. Passenger reading and work attendant lighting.

B. Cabin lighting,entrance lighting and lavatory lighting.

C. Lavatory lighted signs.

A. To depressurize the fuel system at engine shut-down.

B. To provide better fuel filtering.

C. To maintain IDG oil, engine oil and fuel temperature within limits.

A. The Fuel Return Valve colses,

B. The Fuel Return Valve opens,

C. The center tank pumps start.