Through donation.
Definition:
Foreign aid. Foreign aid is money, materials, and services given or loaned by governments, organizations, and individuals in rich countries to help people in poor countries.
Answer:
third option
Explanation:
Crust - 5 to 70 km thick. Mantle - 2,900 km thick. Outer Core - 2,200 km thick. Inner Core - 1,230 to 1,530 km thick.