I have these questions and I'm not sure which formula to use in each: This one is confusing as the distances are in miles rather than kilometers: 1. A car is travelling north along a highway and the driver notices that, although the speedometer reads 60mph he actually covers a distance of 5 miles in 5.5 minutes. Calculate the speed of the car. 2. A child can produce a power of 200W. He has to shovel 1000kg of sand from his drive on to the back of a lorry which is at a height of 0.9m above the ground. What is the smallest energy required to shovel the sand? 3. Calculate the shortest possible time that he would need to shovel the sand on to the lorry.