5 ► The time it takes a kettle to boil some water, t, is directly proportional to the volume, V, of water in the kettle. a Copy and complete the table. 60 1 (seconds) V(cm³) 140 700 500 What is the formula connecting V and t? c How many minutes will it take to boil 1.5 litres of water? 1000 260

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