I don't think there IS a maximum number...for instance, a B-52 has eight of them, and the Marine Corps' CH-53E helicopter has three. The current trend is to put fewer engines on an aircraft for a number of reasons--fewer things to go wrong, lower pilot workload, less expense...
The SBD was a single engine plane. All WWII carrier aircraft were single engine.
The range of a single number is 0.The mode, median, maximum and minimum of a single number is the number.
In chess, the maximum number of possible moves in a single turn is 218.
The maximum number of electrons in a single d subshell is 10.
The maximum number of times the keyword "repetition" can be repeated in a single question is three.
The maximum number of poker players that can participate in a single game is typically 10 players.
The maximum number of options contracts that can be traded in a single transaction is typically limited to 100 contracts.
2 electrons is the maximum number for an single orbital.
2 electrons is the maximum number for an single orbital.
Aircraft engine mounting depends heavily on which airframe is being described. Multi-engine aircraft most commonly have them on the wings, but some also mount an engine on the bottom of the vertical stabilizer. Fighter jets' engines are usually mounted within the rear end of the aircraft, all the way up to the middle of the fuselage. Most single engine private aircraft have their engines mounted on the nose. There are exceptions, of course, but these are the most commonly found configurations.
There is no limit to the number of cells you can merge into a single cell.
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