In the following compound,



the favourable site/s for protonation is/are :

Which of the following compounds will produce a precipitate with AgNO₃ ?

The solution of the differential equation,

$${{dy} \over {dx}}$$ = (x – y)², when y(1) = 1, is :

The number of functions f from {1, 2, 3, ...., 20} onto {1, 2, 3, ...., 20} such that f(k) is a multiple of 3, whenever k is a multiple of 4, is :