Answer:
BC is a minor arc
Explanation:
Just as an extra piece of information that can help us:
Knowing that the diameter splits a circle into halfs, it's degree measure is half of the degree measure of the whole circle: 360/2 = 180 degrees.
This means that diameter AC consists of a 180 degree measure, helping us in the sense that:
mBC + mBA = mAC
mBC + 70 = 180
mBC = 180 - 70
mBC = 110 degrees
Now the mBC to the mBEC is 110: 250 such that we know arc BC is smaller in size as degree measure is proportional to circumference length. Knowing it is smaller in length, BC is thus a minor arc.