If I lose weight, will the stretch marks on my stomach go away?

No. Stretch marks are permanent. Losing weight may make them narrower as the skin shrinks back, but the only way to eliminate stretch marks is to surgically cut away the affected skin.
No. No, they may change but won't go away. Depending on your skin elasticity your skin will react to weight loss differently. Young elastic skin can snap back while less elastic skin tends to be redundant.
No. Sorry, nothing will get rid of the stretch marks except perhaps a tummy tuck which can remove the excess skin and most of the stretch marks.
Probably not. Probably not and unfortunately they may get worse with increase laxity. Sometimes striae look best when placed on tension.
No. Unfortunately, stretch marks do not go away with weight loss. The only effective therapy for stretch mark removal is surgery. Some authors have described mixed results with co2 lasers.