Arc length =
where r is the radius and theta is the angle in radians.
Otherwise,
for theta in degrees.
Similarly,
for theta in radians and
for theta in degrees.
Well, were you taught the formulae I gave you where theta is in radians?
Using those formulae is faster, but since you were given the angle in degrees, you better use that.
Also, you see how I got those formulae where theta is in degrees?
For the arc length, it is the circumference of a circle, multiplied by the angle divided by 360 degrees.
For the area, it is the area of a circle, multiplied by the angle divided by 360 degrees.