Answer:
1. 452.16 square centimeters
2. 150.72 square centimeters
3. 25.12 centimeters
Explanation:
1. the area of the circle
The area of a circle can be calculated with:

The area of the given circle then, is:

or just 452.16 square centimeters.
2. the area of the minor sector
There's a convenient formula for this, but I don't remember it and you don't really need it. A full circle is 360°, and 120° is exactly 1 third of that. 1 third of the size means 1 third of the area:

or 150.72 square centimeters
3. the area of the minor arc
You can do the same thing here. The circumference of a circle is:

So the circumference of the given circle is:

or about 75.36 centimeters.
One third of that:

25.12 centimeters.