Formal Letter To University! Help!?

I am applying to universities such as CAMBRIDGE and UCL and have some questions, I wrote the following letter to send them:

Dear Sir or Madam,

I am portuguese student considering applying to a course at your university, as such I have a few questions wich I would like to ask you :
- In Portugal, secondary school has three years (10,11 and 12). I am at year 11, what is the U.K. equivalent year?
- Our grade scale ranges from 0 (up) to 20. What are the U.K, equivalents? For instance, does A correspond to 17 - 20?
- Do I have to apply to your university a year before I finish high school (that would be at the end of this year) ?
- What grades will you consider in my application? The grades from the three years (10, 11 and 12) or just the first two?
- Does the grade I got at the english language proof my skills in english, or do I have to take a particular test when applying to your university?
- How can I access to a scholarship?
I foward for hearing from you.
Yours faithfully, Ana Rebelo

I AM NOT SURE if I should ask those questions like that, but I see no better way of putting them, organized. Could you PLEASE help me!