Respuesta :

The energy consumption rate of the oven is
3 kW = 3000 W = 3000 J/s.

The amount of energy supplied is
9 kJ = 9000 J

The time that the oven will run is
[tex]t= \frac{9000 \, J}{3000 \, J/s} = 3 \, s[/tex]
(9000 J)/(3000 J/s) = 3 s

Answer:  3  seconds