Consider the following statements regarding Pipes and Cisterns: (A) If a pipe can fill a tank in x hours, the part filled in 1 hour is 1/(1+x). (B) If a pipe can empty a full tank in y hours, the part emptied in 1 hour is 1/y. (C) If an inlet pipe fills a tank in x hours and an outlet pipe empties it in y hours (where y > x), then when both pipes are opened together, the net part filled in 1 hour is 1/x - 1/y. Which of the statements given above are correct?

Three taps A, B, and C can fill an empty tank in 30 minutes, 20 minutes, and 10 minutes respectively. When the tank is empty, all three taps are opened. Taps A, B, and C release chemical solutions P, Q, and R respectively. What is the proportion of solution R in the tank after 3 minutes?

Two inlet pipes J and T can fill a tank in 120 minutes and 144 minutes respectively. If an outlet pipe Z is opened along with them, all three pipes together fill the tank in 240 minutes. How long will pipe Z alone take to empty the full tank?