Colleges in Karnataka

To be eligible to apply in Christ University for BCA course, the basic eligibility for the programme is to pass at +2 level (Karnataka PUC / ISC / CBSE / NIOS / State Boards) from any recognised Board in India. Students pursuing International curriculum must have AIU approval and must obtain a grade of not less than 'C' or it's equivalent.
Good luck.

Yes, you have chances in IITs, as well as BITS Pilani.

Hey Vinay,
If you want to take MBA in Business Analytics, I would recommend you to join some premier institutions like IIM or IITs or at least NITs. In Karnataka, you can apply for MBA program offered in NITK Surathkal Mangalore. You can choose Analytics as your specialisation. Even fees also less compared to any other MBA program also NITK is a brand. If you have valid CAT or CMAT or GMAT Score you can apply for the program. Just click on the below-mentioned link to get more details about the admissions.
https://www.nitk.ac.in/see-also/annoucements/320-admission-to-master-of-business-administration-mba-programme-2019-21

You don't require mathematics as a main subject in order to pursue B.Sc in Economics. But, for B.Sc in Mathematics and Statistics you need Mathematics as a main subject in 10+2.

In case of biotechnology, Maths isn't required but biology subject might be.

This information won't be available here. It depends on the management system of the university.

Hello Prasant,
Yes, indeed. Wisdom School of Management in Bangalore offers different courses in diploma of engineering. I am attaching a link that will give you all the required information about this. You may download the brochure for which link is given in this link, read fully and then decide as to what to do.
https://www-shiksha-com.cdn.ampproject.org/v/s/www.shiksha.com/college/amp/wisdom-school-of-management-bangalore-indiranagar-37032?amp_js_v=a2&_gsa=1&usqp=mq331AQCCAE=#referrer=https://www.google.com&_tf=From %1$s&share=https://www.shiksha.com/college/wisdom-school-of-management-bangalore-indiranagar-37032

Manipal Institute of Technology does not offer Diploma in aerospace engineering but you may do it from a different college and then join Manipal as a lateral entry student for B.Tech in aeronautical engineering.