Three ventilation fans, each working alone, can clear the smoke out of a room in 12 hours, 16 hours, and 24 hours respectively. how long would it take to clear out the smoke in the room if all three fans are used?

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.