Have located the LimeSurvey manual examples for the regular expressions for US Zipcodes and various US an Foreign phone numbers, but have yet to find manual examples or any YouTube videos that could demonstrate or explain either of the following:

1) What type(s) of LimeSurvey questions can be validated with RegEx expressions, e.g. numeric? text? other?
2) How and where to place the appropriate RegEx validation expression within LimeSurvey?

Could someone point me to online documentation or tutorial for how to use RegEX expressions to validate answers submitted in LimeSurvey?

Please refer to the manual.

Question validation - manual.limesurvey.org/Adding_a_question#Field_descriptions

Whole question validation equation - www.limesurvey.org/forum/can-i-do-this-w...zipcode/reply/135114