Came on HI-b visa to USA but never worked,?

I came on HI-b visa to USA but I never worked, now I have applied for green card through my husband ( us citizen ) but USCIS wants all information regarding my work history that I cannot provide. They have given us time for one month, after that our application for green card will denied. What should I do in this situation ? If my green card denied , Can I apply again? Will they ask same questions again? CAn I travel to my country and come back ? In the mean time I have got EAD ( employment authorization ) . Can I start working ? .Except this matter, I dont have any other legal problem. My visa on my passport is expiring next year .