I-864 joint Sponsor

Generally, and based on the information provided her income is enough to sponsor your husband. Herr age will not be a problem,

Is my I140 original copy required to switch the job?

While an I-140 approval notice is the employer's it is helpful to have if not required.

How can i receive money from online store in US without double taxation ?

This is a US Tax law question. You should contact a US tax attorney.

A new employer filing a change the employer petition may use the prior employer I-140 approval where a successor in interest is being processed,...

Is there a minimum time to be in Canada when switching from a tourist visa to a TN?

There no minimum time needed to spend to spend in Canada following a visit to the US to not have trouble when returning on TN unless one overstayed...

Is it 50% or 51% as the minimum?

It is 50% and Control; 51% is easier to show with supporting documentation.

Immigration Question - non-immigrants - Period of authorized stay on the I-94 vs. visa validity

a person is authorized to be in the US for the validity of the I-94

How can I help my mom become a US resident?

A person on TPS may file for a green card in the US if sponsored by a US citizen son or daughter.

I-94 online check

A person may check their US travel history online through cbp website i-94 without consequence.

Can you transfer deceased family member from Canada to USA?

https://help.cbp.gov/app/answers/detail/a_id/237/~/requirements-for-importing-bodies-in-coffins-%2F-ashes-in-urns