For the Wi-Fi, the answer is yes. You can use Wi-Fi anywhere, no matter if you have a cell signal or not.
For Google Voice, no idea, I don't use it.
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,.-~*´¨¯¨`*·~-.¸- Jillian -,.-~*´¨¯¨`*·~-.¸
I've gone to find myself. If I get back before I return, please keep me here
What can I say, I come from race cars and pop rocks