A kettle transfers 1,500 J of energy, 1,200 J to a thermal energy store in the water and 300 J to the air as sound. How efficient is the kettle?

80%

Explanation:

Given data

The energy use is the 1200J transfered to the water

Total energy=1500J

Efficiency = Energy used/total enery

Efficiency= 1200/1500*100

Efficiency=0.8*100

Efficiency=80%

Hence the efficiency of the kettle is 80%

answer: 0.20

explanation: this can only be the answew because all the other measuremnets are not close

igneous rocks also form where plates converge. the subducting plate melts as it sinks into the crust of the earth, and the melt rises into the overriding plate forming volcanoes. metamorphic rocks are formed mainly in the lithosphere, wherever there is high pressure and high temperature. -woods