Find the area of BCD and perimeter of ABD

Which expression gives the area of the triangle shown below

Acircle has a circumference of 7.850 units. what is its radius?

Will mark determine whether the conjecture is true or false. give a counterexample for any false conjecture. given: points r, s, and t conjecture: r, s, and t are coplanar. a) false; the points do not have to be in a straight line. b) true c) false; the points to not have to form right angles. d) false; one point may not be between the other two.