An electric heater supplies 1.8 kW of power in the form of heat to a tank of water. How long will it take to heat the 200 kg of water in the tank from `10^@` to `70^@`C ? Assume heat losses to the surroundings to be negligible.

Explanation

To solve the problem of how long it will take to heat 200 kg of water from 10°C to 70°C using an electric heater that supplies 1.8 kW of power, we can follow these steps:

### Step 1: Convert Power to Watts
The power supplied by the heater is given as 1.8 kW. We need to convert this to watts:
\[ P = 1.8 \, \text{kW} = 1.8 \times 10^3 \, \text{W} \]

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