He should change the direction of the vectors that are tangent to the circle so that each points toward the center of the circle.
B
He should change the lengths of the vectors that point tangent to the circle so that each is the same length.
C
He should change the direction of the vectors that are tangent to the circle so that each points away from the center of the circle.
D
He should change the length of each vector that points toward the center so that it is the same length as the vector pointing tangent to the circle at that point.