The increasing order of the boiling points of the major products A, B and C of the following reactions will be :

Which of the following compounds can be prepared in good yield by Gabriel phthalimide synthesis?

The area (in sq. units) of the region enclosed
by the curves y = x² – 1 and y = 1 – x² is equal to :

The number of words (with or without meaning) that can be formed from all the letters of the word “LETTER” in which vowels never come together is ________ .