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11.  The propeller feathering check is accomplished at:
[[circled]] a. [[/circled]] 1700 RPM.
b. 1500 RPM.
c. Field barometric pressure.

12.  On ignition check, the maximum permissible drop on left or right magnetic is ^[[65]] RPM;  or the difference between the drop off should not exceed ^[[40]] RPM.

13.  The dangerous RPM range which results in empennage vibration is:
a. 1200 to 1600 RPM.
[[circled]] b. [[/circled]] 1300 to 1700 RPM.
3. 2300 to 2550 RPM.

14.  During flight check the RPM on the idle speed check is ^[[500]] RPM.

[[underlined]] POWER SETTINGS [[/underlined]]

15.  The take-off rating from sea level to 4,800' is:
a. 1200 BHP at 2700 RPM and 50" Hg.
[[circled]] b. [[/circled]] 1200 BHP at 2700 RPM and 48" Hg.
c. 1200 BHP at 2700 RPM and 46" Hg.

16.  Should it become necessary to use alternate fuel grade (91/96) in the C-47, take-off power should not exceed 2700 RPM and:
a. 48" Hg.
b. 50" Hg.
[[circled]] c. [[/circled]] 46" Hg.

17.  Rated power for the R-1830-90D engine is:
[[circled]] a. [[/circled]] 41" Hg and 2550 RPM.
b. 38" Hg and 2550 RPM.
c. 41" Hg and 2500 RPM.

18.  Climb power for 75% of normal rated power is:
a. 33" Hg and 2300 RPM.
b. 28" Hg and 2350 RPM.
[[circled]] 3. [[/circled]] 36" Hg and 2350 RPM.

19.  Decision speed is the maximum and minimum speed the aircraft can accelerate to and then stop, depending on length of runway, in the event failure of one engine is encountered.  The minimum value for decision speed should never be less than ^[[88 mph]].  The maximum value should not exceed ^[[safe single engine speed for existing gross wt.]]

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