Pbs Tier 1, Student Part Time Job Pay Is Acceptable,

Hi To All,
I'm student from Pakistan and completed my Bsc (Hons) Degree from UK.
I done 1st two years study in Pak and last two years degree from UK ( Degree awared by UK Uni)
Just woundering do i need to submit my all previous Results(from Pak) and last Year result from Uk OR UK degree and last year result will be enough.

and 2nd question.

I'm doing part time job and include <=20hrs per week.
i have made £23k plus in part time job as Designer and Programmer
My company have monthly basis payroll system so my sallery is calculated from 1st to last date of month which is 4.33weeks (52weeks per year/12 months in Year = 4.33 weeks ()
my payslip shows about 82 hours per month.
( according to home office i'm allowed to work 20 per Month)
question i have can home office raise any question about montly basis payslips that payslips should be 80hours per months.

and what other doc's i should submit and how long home office is tacking these days.
Pls reply