1. The check_web_address function checks if the text passed qualifies as a top-level web address, meaning that it contains alphanumeric characters (which includes letters, numbers, and underscores), as well as periods, dashes, and a plus sign, followed by a period and a character-only top-level domain such as ".com", ".info", ".edu", etc. Fill in the regular expression to do that, using escape characters, wildcards, repetition qualifiers, beginning and end-of-line characters, and character classes. cs.vs. 1196