Aferris wheel turns at a constant speed. it takes 4 minutes to turn through a complete circle. what angle does the ferris wheel turn through in 90 seconds? a) 125 degrees b) 135 degrees c) 145 degrees d) 155 degrees

Okay so as you know a circle is 360 degrees. So let's start by finding what one minute is. 360/4=90 so in 1 minute the Ferris Wheel while move 90 degrees. 90 seconds is equal to 1 minute and 30 seconds so 1 minute/2 (or 30 seconds)=90/2 which is 45. 90+45=135 degrees. 
Side note: I am taking in Geometry right now in 7th grade so I can assure you that this answer is trustworthy. Hope this helps!