An hover craft vehicle operates by moving atmospheric air ( = 1.22 kg/m3 ) with a large fan through the skirt of the vehicle which creates a 3 cm clearance with the ground. If the vehicle weighs 50 kN find a) the required air volumetric flow rate and b) the fan power. (30.6 m3 /s, 54 kW)

Ariver flows from north to south at 8 km/h. a boat is to cross this river from west to east at a speed of 20 km/h (speed of the boat with respect to the earth/ground). at what angle (in degrees) must the boat be pointed upstream such that it will proceed directly across the river (hint: find the speed of the boat with respect to water/river)? a 288 b. 21.8 c. 326 d. 30.2