1, D. The maximum chord length of a circle is m, that is to say, the far diameter is m. If the straight line L intersects the circle, the distance from the center of the circle to the straight line will not exceed the radius at most. 2. In the right triangle BCP, we know that BP 2 = be× BC, and BP=2√ 10 because BC= 10 and CE∶EB=3∶2 and EB=4, so AB=2BP=4√ 10.