The power rating we'll need for this water pump is going to be the work that it does divided by time and the work that it will do is the weight of the water it's going to lift times the height is going to lift it so 'MGH' divided by time and that's 18 kilograms of water times 9.8 Newton's per kilogram times raising at a height of 3.6 metres divided by 60 seconds because it does that in one minute we need that to be in 'MKS' units meaning it’s going to run seconds. And this all works out to 10.6 watts as the minimum power rating you'd need on this water pump and the fifth edition you have 8 kilograms instead of 18 and the height is 3.5 metres instead of 3.6 and the fifth edition answer is 4.57 watts.