If a Denotes the Area of the Sector of a Circle

Multiple Choice

If A denotes the area of the sector of a circle of radius r formed by the central angle θ, find the missing quantity. If
necessary, round the answer to two decimal places.
- $\theta = \frac { \pi } { 4 }$ radians, $\mathrm { A } = 50$ square meters, $\mathrm { r } =$ ?

A) $11.29 \mathrm {~m}$
B) $4.43 \mathrm {~m}$
C) $19.63 \mathrm {~m}$
D) $78.5 \mathrm {~m}$