Right my sister is stook on her radian homework, she tried to make an account on here but it wouldn't let her so I'm posting this for her, I would help her but we haven't studied radians yet!

The questions are:

1) The diagram shows the triangle OCD with OC=OD=17 and CD=30cm. The mid point of CD is M. With centre M, a semicircular arc A1 is drawn on CD as diameter. With centre O and radius 17cm, a circular arc A2 is drawn from C to D. The shaded region R is bounded by the arcs A1 and A2. Calculate, giving answers to 2 decimal places:

(a) The area of the triangle OCD(she worked this out on her own lol) answer being 120cm^2

(b) The angle COD in radians.

(c) The area of the shaded region R.

Diagram-

2) The diagram shows a circle, centre O, of radius 6cm. The points A and B are on the circumference of the circle. The area of the shaded major sector is 80cm^2.

Given that angle AOB=θ radians, where 0<θ<pi, calculate:

(a) The value, the 3 decimal places, of θ.

(b) The length in cm, the 2 decimal places, of the minor arc AB.

Diagram-

She has a few more questions that need answering so can I post them when we get answers for the others? I hate having to type them out

Thanks in advance!