I used meritnation when I was in 12 standard. There are two type of the same site one is free and for second you have to pay. In free one you get the answer of your question from people who is in your standard or above your standard. But for second one you get answer of your question from the expert teacher. They also provide the notes and explain every thing in detail. They provide best teacher at there. It is online so you dont have to go anywhere your teacher send you their best efforts.
