Problem in Software Quality metrics?

Hello everyone, can anyone solve my problem regarding to the software metrics? The details of this problem is follows:

Following are the requirements written for a module “User Login” of a Learning Management system:

Req-01System shall allow user to enter Username in the text box
Req-02System shall allow user to enter password in the text box in encrypted form
Req-03System shall allow user to select type of user (student, teacher, and administrator) from combo box.
Req-04System shall authenticate user when he / she submits username and password on login button
Req-05System should have a good user interface.
Req-06System shall allow user to Reset his username and password when he / she clicks on the Reset button
Req-07System should be user friendly.
Req-08System should be able to perform operations efficiently.
Req-09System shall allow user to remember his username and password by using checkbox.

The requirements listed above are a part of specification document. We want to calculate the lack of ambiguity for the requirements listed above in the “User Login” module. The result will help us in gathering the data for maintaining the metrics for Specification Quality.
You have to analyze these requirements and then you have to find the value for Lack of Ambiguity in these requirements. For this you also have to mention the Functional, Non- Functional, Total and Ambiguous requirements in the given set of requirements.

Where Nr = no. of total requirements, Nf = no. of functional requirements, Nnf = no. of non-functional requirements, Nr = Nf + Nnf
Lack of Ambiguity = Q = Nui/Nr
where Nui = no. of requirements for which all reviewers had identical interpretation (i.e. Unambiguous requirements)

Its important problem for me about examination point of view. Please solve my this problem.
Thank you very much!