1. Find the area of a sector of a circle of radius \(21 \ cm\) and central angle \(45^\circ\).
Area of a sector \(=\) \(cm^2\)
2. The wheel of a motor cycle is of radius \(35 \ cm\). How many revolutions per minute must the wheel make so as to keep a speed of \(66 \ km/h\)?
Number of revolutions \(=\)
(Use \(\pi=\frac{22}{7})\)
(Note: Enter the answers in two decimal places)