How many hours should a 10th class student study??

What needs to be kept in mind to avoid stress? The students should study a maximum of 10 hours a day and a minimum of 7 hours of study is enough for them to pass. We tell them to practice as much as they can through sample papers, and solving them in 3 hours by keeping a watch beside. Feb 27, 2017
https://www.ribblu.com/cbse/papers/class-10