Write regular expressions for both 3a and 3b. Thanks in advance for the help!

3a. [10 points) A variable name in your language consists of lower-case letters Gust a and b for simplicity), upper-case letters Gust A and B for simplicity), and underscores ) It must contain at least one letter, not have more than two underscores, and the first letter that appears must not be upper-case. 3b. 10 points] A loating point number in your language consists of one or more digits, then a decimal point, then zero or more digits, and if there's at least one digit after the decimal point then it may optionally end with e followed by at least one digit (so no minus signs, for simplicity). For example, 1.0, 0., 12.34, 5.6e7, 8.88e58 are all valid, but 23, .1, 4.5e, 6.e7 are not