Ow do I fix a Cromebook tat won't let me click certain keys?

Obviously, as you could see from te spellin errors in tis question, some of te buttons on my Cromebooks keyboard arent workin. Its a Lenovo. I can't spell out te letter keys wit tem not workin so I will put words tat contain tese letters below. Te letters and symbols tat are missin are te ones i can't click.

Letters:
A_riculture
Ast_ma

Symbols:
It_s

Also, I can't use te backspace key, te britness up key, or te volume down key.

I did not drop te laptop or spill anytin on it. I ave already tried turnin it off and back on. Please elp.

Yea

Flip it upside down and bang all the bread and cookie crumbs out. Then hit it with can air. If that don't work, take it to a computer shop.

First of all, make sure that there isn't any kind of debris stuck under the affected keys. Pull the keycaps (if possible) and use a vacuum or canned air the remove/blow out any debris. If that fails, the keyboard most likely needs repair or replacement.

If you don't want to spend the money for a repair, or you just want a "workaround", you can use the "ALT+Number Code" to generate the ASCII symbol.

Look up an ASCII chart to get the number codes. Capital letters are from 65 to 90. Lowercase are from 97 to 122.

http://www.asciitable.com/

Hold down the ALT key while typing in the number code on the numeric keypad.

Decide if it is worth fixing, knowing that it will require a technician and probably cost $200 or so