I need a simple jquery password function

General information for the website: A simple password field and validation.
Description of requirements/features: We have a simple 'create an account' page which we'd like to have added the following:

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'Are you a company?' [checkbox]

If they check this box...

[disable submit button]

[make visible] 'Enter company password' [password field]

If the password is correct enable the submit button so that the company can submit form.

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If they are not a company they won't check the box and the submit button is already enabled to submit form.

The company will have the password which they'll issue to their staff so they can use it on the 'create an account' page. The idea is that a the company staff can create an account only with this pw.

I need delivery by Monday 16th.
Extra notes: