Both types of IUDs work primarily by preventing sperm from fertilizing an egg. The copper IUD releases copper into the uterus, which works as a spermicide. The others release a form of the hormone progestin into the uterus. The progestin thickens the cervical mucus so that sperm can't reach the egg.
Commercial agriculture. Commercial agriculture is a large-scale production of crops for sale, intended for widespread distribution to wholesalers or retail outlets. In commercial farming crops such as wheat, maize, tea, coffee, sugarcane, cashew, rubber, banana, cotton are harvested and sold in the world markets.
Sustainable agriculture can be defined in many ways, but ultimately it seeks to sustain farmers, resources and communities by promoting farming practices and methods that are profitable, environmentally sound and good for communities. Sustainable agriculture fits into and complements modern agriculture.