Boron is used to dope 1 kg of germanium (Ge). How much boron (B) is required to establish a charge carrier density of 3.091e7/cm^3. One mole of germanium has a volume of 13.57 cm^3 and weighs 72.61 gram. Give answer in grams of boron?

I have no idea how to solve this problem. I need help lol.

Oh never mind I figured it out.