12. AABC is a right triangle. If AB = 3 and AC = 7, find BC. Leave your answer in simplest radical form. A 2 square root 3
B 4 square root 3
C square root 58
D 2 square root 13

An insulated thermos contains 148 g of water at 72.7 ˚c. you put in a 11.7 g ice cube at 0.00 ˚c to form a system of ice + original water. the specific heat of liquid water is 4190 j/kg•k; and the heat of fusion of water is 333 kj/kg. what is the net entropy change of the system from then until the system reaches the final (equilibrium) temperature?