On her vacations, Veena visits four cities (A, B, C and D ) in a random order. What is the probability that she visits i) A before B? ii) A before B and B before C? iii) A first and B last? iv) A either first or second? v) A just before B?

In a relay race there are-five teams 'A, B, C, D' and 'E'. a) What is the probability that 'A, B' and 'C' finish first, second and third, respectively. b) What is the probability that 'A, B' and 'C' 'are first three to finish (in any order) (Assume that all finishing orders are equally likely)

A reaction is first order in A and second order in B.How is the rate affected when the concentration of both A and B is doubled?

A reaction is first order in A and second order in B.Write the differential rate equation for the reaction.

The following four compounds A,B,C and D have R or S configurations

A reaction is first order in A and second order in B.How is the rate affected when the concentrated of B is doubled?