Which is not involved in data

From a group of 7 men and 4 women, a committee of 4 persons is to be formed. The probability that the committee has at least one woman is:

What will be come in place of (?) in the given number series.

2, 6, 18, 54, ?, 486

A cone has a height of 12 cm and a base radius of 5 cm. A sphere with the same volume as the cone is constructed. What is the radius of the sphere?

What is the total revenue generated from all products in January?

OCR stands for __________

155, 161, 173, 191, ?, 245

If the homogeneous system of equations

x + y + z = 0

2x + 3y + 4z = 0

has a non-trivial solution, then the value of k is:

3x + 5y + kz = 0

Find the value of x in 5 ^{(5x – 6)}  = 25 ^{(3x – 3)}