Based on Bernoulli's equation, the pressure of the air above airplane wings is a) greater than the pressure below the wings, because velocity of air below is higher than above. b) greater than the pressure below the wings, because velocity of air below is less than above. c) less than the pressure below the wings, because velocity of air below is higher than above. d) less than the pressure below the wings, because velocity of air below is less than above. If two pieces of iron, small and big, were heated for the same time by same way of heating, then a) The heat flow from big to small if they are in contact. b) the big piece has more heat. c) The heat flow from small to big if they are in contact. d) the big piece has more temperature.