What is prove of this equation?

Part a constants huck finn walks at a speed of 0.60 m/s across his raft (that is, he walks perpendicular to the raft's motion what is huck's velocity (speed and direction) relative to the river bank? express your answer to three significant figures and include the appropriate units. relative to the shore)

Acylinder with a movable piston contains 11.7 moles of a monatomic ideal gas at a pressure of 1.32×10^5 pa. the gas is initially at a temperature of 300 k. an electric heater adds 43200 j of energy into the gas while the piston moves in such a way that the pressure remains constant. cp=20.79 j k^−1 mol^−1 for a monatomic ideal gas, and that the number of gas molecules is equal to avogadro's number (6.022×10^23) times the number of moles of the gas. (a) what is the temperature of the gas after the energy is added? (b) what is the change in volume of the gas? (c) how much work is done by the gas during this process?

When doing scientific research ,the sources used should be ?