Billy is trying to shine a laser off a mirror at the end of a basketball court into Sam's eyes to distract him (Billy is evil). Sam is at a 38 degree reflection angle from the mirror. At what angle does Billy need to shine the laser at the mirror to get it in Sam's eyes.

8.29 two streams containing pyridine and acetic acid at 25°c are mixed and fed into a heat exchanger. due to the heat-of-mixing effect, it is desired to reduce the temperature after mixing to 25°c using a stream of chilled ethylene glycol as indicated in the diagram. calculate the mass flow rate of ethylene glycol needed. the heat capacity of ethylene glycol at these conditions is approximately 2.8 kj/(kg k), and the enthalpy change of mixing (δmixh) is given below.