Clutch and sprockets

Two questions (and I understand that various factors impact the out comes but I just trying to get an idea).....

1. How long would you get from a set of sprockets? Kilos or miles distance.

2. Clutch...how long should it last....I know there is a second clutch adjustment mid way down the cable....but I'm wondering how much distance I could expect. Assume old man riding

Thanks in advance