The mineral we call diamond is the hardest known substance on earth. explain why attaching small pieces of diamond to the tips of saw blades and drill bits makes the best type of tools for cutting through hard objects.

Explanation:    Diamond is one of the forms of carbon compounds, where carbon atoms are arranged in a crystal structure, called a diamond cube. Thus, the arrangement of carbon atoms in a three-dimensional diamond cube with very strong covalent bonds is why the diamond is a very tough mineral. Due to this structure, the diamond is a huge covalent compound where each carbon atom is joined by four other atoms, and then the atoms form a very regular tetrahedral structure. It should be said that in the diamond there are no free electrons and other free particles, so the diamond does not conduct electricity. In order to break up very strong covalent bonds between carbon atoms, a very high temperature is required, so the diamond has a very high melting point. Therefore, the diamond is used for attaching to the top of saw blades and drilling tools due to its high hardness and high temperature resistance. It is also used as an abrasive for polishing, in the oil and mining industry.

it is very hard for the climatologists to precisely predict how will the global temperatures be changing so there's lots of models, some of which differ significantly, this is due to multiple factors, and probably the most important is the human activity.

humans have been a key factor in climate change around the globe since the start of the industrial revolution, and in the past few decades the consequences are becoming more obvious. there's lots of emission of pollutants in the atmosphere as well as changing the environment on the surface itself, so it's really hard to predict how will that go in the future because there's some countries that are reducing the damage and are going towards green energy, while others are stubbornly continuing with pollution and damages to the environment.