Mechanical Engineering

The fee depends on in which institute you want to take admission. And the eligibility for mechanical engineering is to have science stream in class 12th along with maths, obviously. Other than that, various institutes have their own entrance examinations based on whether they are government or private. For government institutes, you need to achieve a decent rank in JEE Mains for some good colleges of the nation.

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Please check for Eligibility criteria to pursue M.Sc in environmental science. If you qualify, you can apply to various colleges for PG in environmental studies.
As a minimum criterion of eligibility, aspiring candidates need to have completed:
Higher and Senior Secondary levels of education (classes X and XII) with a minimum aggregate score of 60%.
Graduation in Science/ Engineering/ Economics/ Mathematics/ Statistics/ Geology/ Geography, with a minimum aggregate score of 60%.
Often, candidates are required to qualify an institute, state or national-level entrance test for admission to the course. Regards.

First clear TOEFL, SAT, GRE with a good score and it is also suggested to clear GATE tests but I can't assure that these were enough because rules and regulations and also eligibility criteria vary with the universities but most of the top universities accept these tests for admissions.

If you are interested in MBA then definitely go for it. MBA is really a good course. You will learn a lot of good things in MBA that boost your career in the field you want.

Placements is average in RU is average. Academics and placements training is provided, which will help in placements.

Check out the link below for details:
https://www.shiksha.com/engineering/colleges/diploma-mechanical-engineering-colleges-Mumbai-all.