hello namrata 

yes a student can get a good placement depending his/her performance during the b.tech course though if his/her marks are not so good during 10th and 12th.if u have involved yourself in various activites other than academics and have work experience in the form internships and all there are chances of selection.

You can, if u hv good performance in the college.

You just have to impress them. They don't saw your marks ,they want you to have a special ability to know things better

Yes offcourse.

For getting job what does really matters ??

Your academics in engineering matters much more as compared with your school academics.

Good luck !!!

Dear

Most of the top IT companies require and demand good grades overall in the placement time.That time you won't get A grade companies but if get good grades overall in engineering and obtained all the knowledge, skills and expertise then after few years then you can apply for top IT companies.So be positive and give your 100% in study .

All the best

Depends on your skills & company recruiters.. At least 60% is cut off for companies..