(a) neil a. armstrong was the first person to walk on the moon. the distance between the earth and the moon is 3.85 × 108 m. find the time it took for his voice to reach the earth via radio waves. (b) someday a person will walk on mars, which is 5.60 × 1010 m from the earth at the point of closest approach. determine the minimum time that will be required for a message from mars to reach the earth via radio waves.

The cerebellum controls? thirst sensations sleep-wake cycles hand-eye coordination heart rate and pulse

Apulley system is used to lift a 2,000 newton engine up a distance of 3 meters. the operator must apply a force of 250 newtons to the chain of the pulley system to lift the motor. to lift the engine 3 meters, the operator must pull a total of 30 meters of chain through the pulley system. what is the value of di?

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.