Explanation:
Power of electric kettle, P = 1 kW
Voltage, V = 220 V
(a) Electric power is given by the formula as follows :

R is resistance

(b) When connected to a 220 V supply, it takes 3 minutes for the water in the kettle to reach boiling point.
Energy supplied is given by :

P is power, 

Answer:
a. 250kg I think it's the right answer. hope it helps:)
Answer:
because there is external pressure is less in the height.
hope it helps.
(20 miles) x ( 1/45 hour/mile) =
(20/45) (hour) = <em>
4/9 hour = </em>26 minutes 40 seconds