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You do not have to enter take off speed. You can read more about take off here (example for Cessna 172).
The takeoff speed of such aircraft like 737 varies quite a bit, depending on the takeoff weight and the use of high-lift devices like flaps and slats. However, a good average speed range is about 160 mph (260 km/h) to 180 mph (290 km/h).
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