Answer:
I think its the last one
Explanation:
its supposed to be H 2 O 2.
Answer:
A budget is an estimation of revenue and expenses over a specified future period of time and is usually compiled and re-evaluated on a periodic basis. Budgets can be made for a person, a group of people, a business, a government, or just about anything else that makes and spends money.
There are 115 known elements as of today (Feb. 13, 2016)
so, 'C' is the correct answer
The reaction of a metal with oxygen to form rust is called as redox reaction.
Explanation:
The process during which the surface of metal reacts with the oxygen ions present in air, it has tendency to get oxidized that is formation of an oxide layer on the surface of the metal. Generally, it occurs when metals like iron comes in contact with moisture or water. So the oxygen in moisture reacts with iron giving its electron and getting oxidized and reducing the surface of metal by forming metal oxide. So the complete process of formation of rust is termed as redox reaction. As here both oxidation and reduction is taking place.