What is the value of positive square root of $$\ 14+ 6\sqrt{5}\ $$?

Study the following graph and answer the question that follow.

What is the approximate average number of candidates passed from all the institutes together?

A tower standing on a horizontal plane subtends a certain angle at a point 160 m apart from the foot of the tower. On advancing 100 m towards it, the tower is found to subtend and angle twice as before. The height of the tower is

Speed of train B is 20% more than speed of train A and length of train A and B is 720 meters and 600 meters respectively. If both trains running in opposite direction cross each other in 24 second, then find speed of trains B (in km/hr)?

Find k, if the line 2x - 3y = 11 is perpendicular to the line 3x + ky = -4? 

A watch which gains uniformly is 4 minutes slow at 9 A.M on Sunday and is 4-minute 15 sec. fast at 9 P.M on the upcoming Friday. When was it correct? 

6 litres are drawn from a cask full of wine and it is then filled with water. 6 litres of the mixture are drawn and the cask is again filled with water. The quantity of wine now left in the cask is to that of the water in it as 121 : 23. How much does the cask hold?