Can someone tell me which formula to use here? (time to boil water)

[yuheng_wu]

Homework Statement

Can someone tell me which formula to use here

Relevant Equations

P = W/Δt <=> Δt = W/P = Q/P.
Q= I evaporate water . m
This is the only formula I'm thinking of, but it doesn't work here I think

An amount of water at a temperature of 20 °C is passed through a water boiler in 1.5 min to
brought to boiling point. The kettle is broken and does not jump off.
The time between the moment when the water reaches boiling point and the moment when all the water
is evaporated, is equal to:
a) 7,5 min.
b) 4,5 min.
c) 10 min.
d) 15 min.

 

[kuruman]

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