Open cascading sets of URLs using PowerShell

* To be considered, please demonstrate that you understand my requirements. * Requirements 1) Each time the script is run, open cascading sets of URLs in a single instance of IE. 2) isSiteOpen should determine whether a URL is open that contains a specified string. 3) OpenSites should determine how to open URLs: the first in each set should be opened in a new tab; successive URLs should be opened in background tabs. 4) If IE is already open when the script is first run, preserve existing URLs. 5) The script should be compatible with PS 2 (Windows 7) and PS 5 (Windows 10). Known Issues 1) If IE is open on the 1st run, the script will substitute any URLs that are open with the two Google URLs. 2) On the 2nd run, the script checks if a URL is open that contains "google", but it requires both Google URLs to be open before it will open Microsoft. 3) The script throws errors in PS 5 (Windows 10).