The diagram shows a gear train.
 

The mechanical advantage of the gear train is 1.6 : 1 with an efficiency of 80%.

Calculate the number of teeth on the driven gear.   (3 marks)

To change a tyre on a bus, a system of pulleys, as shown, is used to lift the wheel and tyre to re-fit them back on the bus. The wheel and tyre have a combined mass of 95 kg.
 

What effort is required to lift the wheel and tyre if the efficiency of the pulley system is 80%?   (3 marks)