To get an A* in Biology OCR?

What percentage do you need to achieve overall? What happens if you get A in the A2 coursework but a B/C in the AS coursework?

At AS unit 1 is 30% unit 2 is 50 % and the practicals are 20%.

Say someone got 80% A and 20% C

and then for A2 they got:

Unit 1 - A, Unit 2 - A and Practicals A - What would it probably average out to? (and got above 90% in the A2's)

last year unit 1 : 79 UMS
unit 2 : 250
course work 24 ums (equivalent to 21 raw marks) i have retaken this and got 30 RAW marks
this year course work 32 RAW marks

can someone please tell me what i need to get in my unit 1 and 2 exams for A2 to get an A overall and how much i would need to reach an a*

basically here are my bio statts

last year unit 1 : 79 UMS
unit 2 : 250
course work 24 ums (equivalent to 21 raw marks) i have retaken this and got 30 RAW marks
this year course work 32 RAW marks

can someone please tell me what i need to get in my unit 1 and 2 exams for A2 to get an A overall and how much i would need to reach an a*

( I got an A at AS)

I doubt you got 250 UMS for F212, as the paper is up to 150 UMS. Did you get 150 UMS, or something similar? Until I know that, I'm going to assume you got exactly an A at AS

You need 240/300 for an A and 270/300 for an A* in A2 alone. It needs to add up to 480/600 UMS overall.
I got 32 marks in my coursework as well, and both my teacher and I are working on the assumption that 32 will be the B grade boundary for this year, so assume you get 42/60 UMS from the coursework.
You can get 240/300 UMS from exams, so to get an A you'll need 198 UMS from them both (82.5%). To get an A* you'll need 228 UMS from them both (95%), or it's easier to think of it as you can lose a maximum of 12 UMS from the exams.

Why make it so complicated? You need at least 480/600 overall and at least 270/300 from A2. Theoretically you can get 0 on the AS practical unit and still get an A*.

If you get 0 at the AS practical doesn't that mean you need full ums from both unit 1 and unit 2?