+633 This isn't as much calculus as it is geometry, but I'll explain here.
Areas of sectors are in general the area of the circle times the proportion of the circle you are measuring the area of.
For question (a), given a radius of 7 (72 being 49), it would be \(49\pi\times\frac{71^\circ}{360^\circ}\), or 49pi*71/360 ≈ 30.360002338441363
For question (b), given a radius of 10 (102 being 100), it would be \(100\pi\times\frac{0.3\text{ rad}}{2\pi\text{ rad}}\), or 100pi*0.3/(2pi) = 15.
Hope I managed to get the answer to you in time :)
