can u plzz tell me what topic should i study more in organic chemistry,physics2 and maths especcialy

general organic chemistry is most important,and should focus on mechanism of all the reactions.they can ask complete organic chemistry.but i suggest u to emphasis on the topics like-cannizaro , aldol , hoffmanbromamide , carbene , nitrene , E2 ,sn1 , sn2 , are some of the important topics

I feel these r the important topics are.

Maths:      calculus, Vectors, Complex numbers, co-ordinate geometry(2D+3D) Quadratic equations.

Physics:    Optics, Modern physics, Thermodynamics, A/C circuits, Fluid mechanics, Experiments.

Chemistry:
         Solid state, chemical bonding, Aldehydes, ketones, carboxylic acids, Alkenes,
         alkynes, stereo and geometrical isomerism, transition elements, coordiantion compounds,
         electro chemistry, kinetics and equilibrium.
but I will suggest you to cover alll the topics and give more stress on above given topics.