Please complete problem 1-4. Thanks 1. The energy required to increase the temperature of unit mass of a substance by one unit is called its 2. The type of heat exchanger in which steam directly mixes with the product is called a. heat exchanger 3. TRUE / FALSE - For the same heat flux across two slabs of the same thickness, the temperature difference across the slab of higher thermal resistance will be lower than that across the slab of lower thermal resistance 4. TRUE / FALSE - For forced convection during flow in a pipe, Prandtl number increases with an increase in mass flow rate of the product