If cosec θ=1.25 then $$ {4 \ tanθ-5 \ cosθ + 1\over secθ+ 4cotθ-1}=?$$

Direction : What value should come in the place of question mark (?) in the following questions?

$$ \sqrt{8281} =(?) $$

In the figure given below, PT=6 cm and PA=4 cm. What is the length of AB?

A shopkeeper marks the price of an item keeping 20% profit. If he offers a discount of $$12{1\over 2}\%$$ on the marked price, his gain percent will be 

Water flows in to a tank 15 m.×10 m. through a rectangular pipe 2 m.×1.5 m. at 20 km./hr. In how much time will the water level in the tank rise by 3m.?

Running at a speed of 60 km per hour, a train passed through a 1.5 km long tunnel in two minutes, what is the length of the train?

Milk and water are mixed in vessel A in the ratio of 5:2 and in vessel B in the ratio of 8:5. In what ratio should quantities be taken from the two vessels so as to form a mixture in which milk and water will be in the ratio of 9:4 ?