I want abs and do about 100 to 150 sit ups a day and want to know how long it takes?
It takes a looooooong time. And you will have to do a lot more than sit ups. Plank, leg raises, bicycle crunch just to mention a few. Not only that but you need to do exercises let squats and deadlifts to acheieve a good looking 6 pack. You have to train your obliques as well. Plus throw in some hiit cardio on top a healthy clean diet. It takes a lot of dedication. Here's a link to a guide http://www.bodybuilding.com/fun/30-days-to-6-pack-abs.html
Depends on how intense your workout is, is u gov up at the first sweat drop or first sign of muscle pain in this case abs, then never... but if u push to the max then faster
Took me 2 years i had a body very similar to yours but every day wen i got home i would sit down and do an ab routine 4 about 30 mins