Explanation:Sources are previously published writings that can be used as evidence to support your essay. It is important to use sources when writing an informative essay because it is a way of showing that you have investigated and researched about the topic you want to inform. It is also a way to include a variety of viewpoints.
The sentence is in active voice. The passive voice form of this sentence would be “How much money is saved by you in a year?” Active voice consists of a transitive verb.