A sector is cut-off from a circle of radius 21cm. The angle of the sector is 120°. Find the length of its arc and the area.

The perimeter of a sector of a circle of radius 5.7m is 27.2m. Find the area of the sector.

The perimeter of a certain sector of a circle of radius 5.6m is 27.2m. Find the area of the sector.

The minute hand of a clock is cm long. Find the area described by the minute hand on the face of the clock between 7.00AM and 7.05AM.

The minute hand of a clock is 10cm long. Find the area of the face of the clock described by the minute hand between 8AM and 8.25AM.