Homonym: r (Response)
The letter "r" is the 18th letter of the English alphabet. It is a consonant and is pronounced as /ɑːr/ in American English. In writing, "r" can appear in various positions within words, such as at the beginning, middle, or end. It is commonly used in many languages and has different pronunciations depending on the language.
In the context of mathematics, "r" often represents a variable, such as the radius in geometry. In statistics, it can denote the correlation coefficient, which measures the strength of a relationship between two variables. Additionally, in programming, "r" is used in languages like R for statistical computing and data analysis.