3) Exceeding question A ball is launched from a cennon at some angle e. The moment it leaves the cannon, it has a velocity in the x direction of 20m/s, and a
velocity in the y direction of 50m/s. What angle was the cannon fired at? Show
work in the box below. (hint, recall properties of right triangles)

Air is to be preheated by hot exhaust gases in a cross-flow heat exchanger before it enters the furnace. air enters the heat exchanger at 95 kpa and 20°c at a rate of 0.6 m^3/s. the combustion gases (cp = 1.10 kj/kg°c) enter at 160°c at a rate of 0.95 kg/s and leave at 95°c. determine the rate of heat transfer to the air and its outlet temperature.

What is the specific heat of wood ?

Explain the difference in reactivity of the elements based on their electron configurations.