Dimethicone, also known as polydimethylsiloxane, is a silicon-based polymer that is a man-made synthetic molecule made up of repeating units called monomers. Silicon is the second most abundant element in the Earth's crust after oxygen, and silicon dioxide is also known as sand, commonly found on beaches and shores.
In regards to a job, a refusal letter is written when a company offers a position to an individual who must refuse due to his or her circumstances, such as already having accepted another offer, or simply a lack of interest in this particular job.
A letter of reprimand is a United States Department of Defense procedure involving a letter to an employee or soldier from his or her superior that details the wrongful actions of the person and the punishment that can be expected. A Formal Letter of Reprimand is one in which a copy of the letter is kept on record. In military contexts, a formal letter of reprimand can be career ending, even without prescribed punishments, because it makes it difficult to secure advancements in rank or to enjoy the respect of one's peers. In legal contexts, a letter of reprimand is sometimes called a letter of admonition.