If the radius of a circle with center 0 is 15.5, and the measure of angle aob is 90, what is the length of arc ab?
7.75
7.75π
10
10π

i'm stupid when it comes to math.
surprised i made it here.

Can someone me i’m confused. will give brainliest and a whole bunch of points

Which of the following best describes the delian problem?

Three friends went on a road trip from phoenix, az, to san diego, ca. mark drove 50 percent of the distance. jason drove 1/8 of the distance. andy drove the remainder of the distance. 1. andy thinks he drove 1/4 of the distance from phoenix, az, to san diego, ca. is andy correct? 2. the distance from phoenix, az, to san diego, ca, is 360 miles. how many miles did each person drive? 3. solve the problem. what is the answer in total?