We are given that a snowboarding rail is an arc of a circle in which BD is part of the diameter. Let's take a look at the given diagram. Notice that AC is a chord of the circle.
Since we are given that arc ABC is about 32 % of a complete circle, the measure of this arc will be 32 % of the measure of the whole circle, 360^(∘).
The measure of the arc ABC is 115.2^(∘). Now let's recall that if a diameter of a circle is perpendicular to a chord, then it bisects the chord and its arc. This means that mAB will be half of mABC.
mAB=1/2*115.2^(∘)=57.6^(∘)
The measure of arc AB is 57.6^(∘).
