Lilac Lake Park, located in the northwest of Shenyang, is the largest artificial lake in Shenyang. Artificial lakes have the function of "absorbing heat", which can greatly weaken the surrounding areas in hot summer.

(1) Urban construction of artificial lakes can beautify the environment, and because the specific heat of water is relatively large, the temperature changes little when absorbing or releasing heat, and the ambient air temperature can be adjusted.

(2) The heat absorbed by lake water is q = cm △ t = 4.2×103kg/m3× 5×107kg× 2℃ = 4.2×10/0J.

So the answer is: large specific heat capacity; 4.2× 10 1 1.