Which of these are stable and unstable

Imagine that you own a property that is exactly 2.2 acres large. you want to sell your property, but your realtor tells you that you cannot sell your land by the acre. in order to sell your land you need to determine the area you own in units of square meters? given that there are 1.6 kilometers in 1 mile and 640 acres in 1 square mile, what is the area of land that you own in square meters square meters?

How many liters of oxygen gas, at standard temperature and pressure, will react with 35.8 grams of iron metal? 4 fe (s) + 3 o₂ (g) → 2 fe₂o₃ (s)

Acompound has a molecular weight of 12.124 atomic mass units and the empirical formula c3h40. what is the molecular formula of the compound?