What is the name for elevation difference between two adjacent contour lines

answer: option d : 3.85 units

step-by-step explanation: in the given figure the blue line is diameter   .the diameter is the blue line which equals 7.7 units.radius is half of diameter .radius = 7.7÷2=3.85 units.

option d is the right answer.

explanation:

mark brainliest and have a great dayz1

answer; ///i believe the correct answer to the above question is; ///(drainage basin;