You are given a math word problem and you are supposed to make use of mathematical concepts like probability, combinatorics, linear equations, sequences/series, or simple operators like addition, subtraction, division, or multiplication to answer the given question. Choose the best option from the 5 given options and report that option.

Question: A leak in the bottom of a tank can empty the full tank in 6 hours. An inlet pipe fills water at the rate of 4 liters per minute. When the tank is full in inlet is opened and due to the leak the tank is empties in 8 hours. The capacity of the tank is?

 Option A: 5768

 Option B: 5760

 Option C: 5762

 Option D: 5766

 Option E: 5712
Option B

Question: A train covers a distance of 12 km in 10 min. If it takes 10 sec to pass a telegraph post, then the length of the train is?

 Option A: 100

 Option B: 110

 Option C: 200

 Option D: 130

 Option E: 140
Option C

Question: Find the average (arithmetic mean) of x and y if the average of x, y, and 5 is 20 more than the average of x, y, 5, and 15.

 Option A: 110

 Option B: 120

 Option C: 130

 Option D: 140

 Option E: 150

Option D