The vertical sections of the wing of a fan are shown. Maximum upthrust is in

The vertical cross-section of a cone is

The vertical cross section of a cylinder is…….

Fig. represents vertical sections of four wings moving horizontally in air. In which case the force is upwards

An electric fan rotates 100 times in one second. If the length of its wing from its axis of rotation is 0.5 m . Then the speed of the fan is ______ m s^(-1)