When 3.00 g of a substance 'X' is dissolved in 100 g of CCl₄, it raises the boiling point by 0.60 K. The molar mass of the substance 'X' is ______________ g mol^$$-$$1. (Nearest integer).

[Given K_b for CCl₄ is 5.0 K kg mol^$$-$$1]

The sum of all those terms which are rational numbers in the

expansion of (2^1/3 + 3^1/4)¹² is :

The first of the two samples in a group has 100 items with mean 15 and standard deviation 3. If the whole group has 250 items with mean 15.6 and standard deviation $$\sqrt {13.44} $$, then the standard deviation of the second sample is :

If $$f(x) = \left\{ {\matrix{ {\int\limits_0^x {\left( {5 + \left| {1 - t} \right|} \right)dt,} } & {x > 2} \cr {5x + 1,} & {x \le 2} \cr } } \right.$$, then