3 weeks for her knee (im presuming nothing else wrong with her?) The only issue she would have is getting to work, so taxi or her dad maybe? As a single woman living alone, im sure she could afford a taxi to work or maybe even see if one of her colleagues could give her a lift in exchange for a few quid?
A lady at my work did her ankle in, she had probably 2 months off but we do alot of running around, heavy lifting so a completely different job to Angela where she is on the phones all day or sat at her desk.
I hope its played on her mind that maybe if she lost weight, her joints wouldnt be so bad. At her size, her knees must be under so much pressure just to keep her standing.