What is the angle and Angular Speed?

The earth’s radius is about 4000 miles. Kampala, the capital of Uganda, and Singapore are both nearly on the equator. The distance between them is 5000 miles.

Through what angle do you turn, relative to the earth, if you fly from Kampala to Singapore?

α =5000/4000 =1.25rad
=> α= 1.25*180/π = 71.62^o

2) The flight from Kampala to Singapore takes 9 hours. What is the plane’s angular speed?

The angular speed  :
ω =α/t =1.25 /(9*3600 )= 3.858×10^-5  rad/s