We have four gears with below features=> Both Gear A and D has 60 teeth=> Gear B has 40 teeth=> Gear C has 20 teeth=> Every two minutes, Gear B makes 25 full turns.What is the relative speed of Gear A and Gear B?

Spatial Science Riddle

Both A and D will rotate at Same speed. Gears of the equal size will rotate at constant speeds despite or any sized gears in between them.