Alarge boulder falls from a cliff located 1,044 meters away from a herd of elephants. the temperature of the air is 29°c. how long after the boulder crashes will the elephants hear the sound? a. 319 m/s b. 331 m/s c. 343 m/s d. 219 m/s

A1500 w electric heater is plugged into the outlet of a 120 v circuit that has a 20 a circuit breaker. you plug an electric hair dryer into the same outlet. the hair dryer has power settings of 600 w, 900 w , 1200 w, and 1500 w. you start with the hair dryer on the 600 w setting and increase the power setting until the circuit breaker trips. under what setting does the circuit breaker trip.