CBSE 10th

Yes, You get placed if you have good coding skills as well as Development skills.Generally, Companies Focuses on your skill, not Your 10th or 12th marks. But You Engineering marks they see but If you are good at above both skills then marks of academics become secondary.

This is depend on u and your choice. If u interested in CA than choice College. The choice of subject for graduation will depend upon the subjects you have studied in your graduation. Now concerned to your marks in 12th standard, 48% marks are less for good institutions. But now a days there are many private colleges and institutes and universities, which offer many career oriented courses. You could try in such institutions, but you have to SEE the minimum marks required by the university.

Hi, For joining B.Tech for environmental Engineering you have complete 10+2 I. e. your 11th,12th with Science stream or either go for Diploma + degree after 10th. This way only you can get admission for B.Tech degree for Environmental Engineering.

Yes you can do diploma in computer engineering after 10th. Admissions in asked Polytechnic are carried out through centralized admission process by the Directorate of technical education, Maharashtra State, Mumbai. Hence apply through DTE Maharashtra website as given below.
http://www.dtemaharashtra.gov.in/

MORE THAN 82% TO GET admission.