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. what power setting caused the breaker to trip?

900 W.      

Explanation:

Given that

Electric heater 1500 W

We know that power P given as

P= V I

So the total power of 120 V and 20 A circuit

P = 120 x 20

P= 2400 W

So the power new load P'

P'= Total system power(P)- Electric heater load

P ' = 2400 - 1500

P'= 900 W

So the answer is 900 W.

i would think it's food chain

answer: the exterior temperature of commercial jet planes as they leave the stratosphere and return to the ground increases steadily.

explanation:

the lower most layer of atmosphere is troposphere which extends from 0 to 12 km above the surface of the earth. the temperature initially decreases as distance is increased from the earth's surface. commercial jets fly in lower part of the stratosphere. the stratosphere extends upto 50 km. the temperature in stratosphere starts rising again due to presence of ozone which traps the uv rays.

thus, when the planes leave the stratosphere and return to the ground, the exterior temperature increases steadily.