Manhole A is at 1+00 and the surveyors log is marked 55.00 ft. Manhole B is at 2+50 with an elevation of 50.5. What is the slope?

Manhole A is at 1+00 and the surveyors log is marked 55.00 ft. Manhole B is at 2+50 with an elevation of 50.5. What is the slope?