M.Sc

The below mentioned are the renowned institutes as per your requirements:
1. Tata Institute of Fundamental Research.
2. Chennai Mathematical Institute.
3. Indian Statistical Institute.

Hi,
You can pursue M.Tech from any of the IITs, BITs, etc. You can appear for NET, UPSC, B.Ed, research or Ph.D.

Nowadays, most of the universities allow B.Tech only for M.Tech.

Yes, you can do that. Every institute have different eligibility criteria to apply for M.Sc mathematics and you will have to appear for the entrance examination after fulfilling the application eligibility criteria.

Good, M.Sc microbiologists have a wide range of industries to apply like pharma, Biotech, Agriculture, food processing, dairy, leather, water, research, etc.

First of all, almost everything today is IT based, so there is no question regarding value in this field. Secondly, what type of job you want to do is important, whether to be an HR, Admin or Technical in IT field it's is all up to you. Just relax and think where you want to apply your knowledge

Dear,
First, you decide where you want to land up, what you wants to be, which field you prefer to work and you fill be comfortable for you. Select that field. Salaries depends on your ability and not course you select. Opportunities are different in different fields. Field which is giving one high salary and job Satisfaction, may not be same for some one else.