How much weight would I lose if I only drank diet coke with no food for 3 weeks?

I'M NOT PLANNING ON DOING THIS.
Me and a friend were having a discussion and this question just randomly came up.
So basically, we want to know if someone was about 152 lbs(11Stone) and you only drank diet coke for 3 weeks with no food. How much weight would you lose?

Just want to emphasise that neither of us were planning on doing this. Food is too nice.

You would die. At most, 5 lbs of water weight but pop is water so...you wouldn't lose weight.

Your body would go into starvation mode and keep your body fat cause it sees that it's not getting any food.

You would actually lose weight, but you would likely die too. You'll be malnourished for sure from lack of macro and micronutrients. The brain specifically needs glucose to run. Your body can shift to using fat via ketone body metabolism during starvation states, but the brain will still require a certain percentage of energy from sugar despite the shift in metabolism.

Your body will ultimately start breaking down protein as a substrate to make glucose. Look up marasmus.

I think that’s not a good idea because it’s not good for your health and you should never lose more than 1 - 2 lb per week. If you want to lose weight join a gym and do it properly.

Why you want to lose your weight using diet coke and leaving the foods.
It is not a good idea for the weight loss because using only coke can be harmful for your stomach.
If you want to lose your weight through water foods then you should use fresh fruits juices, vegetables soups, and green tea etc. for the effective weight loss.

I am a stout fellow and I lost over 16 st on a water, lemon juice and bread diet back in 1988. Unfortunately I regained the weight and have since added another 10st. My present weight has remained steady for the last five years. I am now 52st.

lol you don't know how starvation works do you?