We all know that cars and factories produce a lot of greenhouse gas. Not many of us know that livestock such as cows, deer and goats also create emissions. These farm animals are responsible for a lot of the world's methane. This is the most common greenhouse gas after carbon dioxide (CO2). Billionaire Bill Gates decided to do something about the methane these animals belch out. He invested in a technology start-up that aims to reduce the amount of methane coming from animal burps. The tech company is called Rumin8. It is located in Australia. It has now created a synthetic, seaweed-based dietary supplement for animals. The company says its supplement stops the creation of methane in animals' stomachs.

Bill Gates is the co-founder of the tech giant Microsoft. He spends a lot of his money on projects that help the environment. He believes the farming of animals for meat should be reduced because of the impact it has on climate change. He says one third of all greenhouse gas emissions comes from livestock production. A spokesperson for Mr Gates' energy investment company spoke about the benefits of the new synthetic dietary supplement. He said: "Rumin8 offers a low-cost toolbox that has already proven to be effective in reducing emissions." He added: "Our team will support Rumin8 in working closely with farmers to expand the reach of this solution globally."