The value of $$ \sqrt { 2^4} \ + \ ^{3}\sqrt {64} \  + \ ^4\sqrt { 2^8} \    $$ is :

A person swims a distance of 28 km. in the direction of stream in 5 hours and a distance of 13 km. in 5 hours against the stream. What is the velocity of the stream?

If  tan²θ +cot²θ  = 2, then what is the value of  2^{secθ cosecθ}?

A man had a certain amount with him. He spent 20% of that to buy an article and 5% of the remaining on transport. Then he gifted ₹ 120. If he is left with ₹ 1,400, the amount he spent on transport is: 

The least value of n, such that (1 + 3 + 3² + ... + 3ⁿ) exceeds 2000, is-

If x+y=10 and xy=4, then what is the value of x⁴+y⁴=?

An Aeroplan flying horizontally at a height of 3 km. Above the ground is observed at a certain point on earth to subtend an angle of 60 °. After 15 sec flight, its angle of elevation is changed to 30 °. The speed of the Aeroplan (taking √3 = 1.732) 

Each question below is followed by two statements A and B. You have to determine whether the data given in the statement is sufficient for answering the question. You should use the data and your knowledge of Mathematics to choose the best possible answer.
Give answer (A) if the statement A alone is sufficient to answer the question, but statement B alone is not sufficient.
Give answer (B) if the statement B alone is sufficient to answer the question, but statement A alone is not sufficient.
Give answer (C) if both statements A and B together are needed to answer the question.
Give answer (D) if either the statements A alone or statement B alone is sufficient to answer the question
Give answer (E) if you cannot get the answer from the statements A and B together, but need even more data.

Triangle ABC has angle BAC equal to 90°. What is the measure of the angle ABC?
A. The angle ACB is 35°
B. The angle CBA is 55°