se p$,$ q$,$ r and logical operators to express the following system specifications.

i$.$ The user has paid the subscription fee, but does not enter a valid password.

ii$.$ Access is granted whenever the user has paid the subscription fee and enters a valid

password.

iii. Access is not granted if the user has not paid the subscription fee.

iv$.$ If the user has not entered a valid password but has paid the subscription fee, then

access is granted.