Lucky BrandWomen's Emmie Ballet Flat

Would these hold up to a 10 hour work day where I am on my feet most of the day without leaving my feet hurting or the shoe falling apart from wear?

are these able to foldup for packing?

What is the difference between b(m) and c/d?

Do these run true to size? I normally buy a 7 - 7 1/2 shoe.