In a programming language a variable is represented as a string of at least

four characters with the following requirements. The variable must start with

a $$,$ and end with the digit $7,$ and it must contain at least one letter, and all

letters must be before digits. For example, $$1237$ and $$7$ are valid

ways to represent two variables but $$5$$ and $1$ are not. Give a regular

expression over alphabet $\{,,,,,0,1,2,3,4,5,6,7,8,9,$ $$,\%\}$ that defines all

variables with no even digits or vowels.