- Yes, she can. (Friends on an H-1B got single entry Canadian visa.)
She will have to show proof of status in the US.
You have to create an account here, upload all the required documents (tax returns, proof of status, itinerary, etc), pay a fee and wait for a decision. After decision is reached, she will be able to mail in her passport.
Take into account that if your main income is in China, you will likely need some of the documents translated to English/French to apply for a visa.
The processing time varies. For them it was ~60 days in 2013 (From the start of collecting the documents to receiving the passport with a visa). You will be without your passport for the second part of the application process.
Depends on the processing time by the place where you apply. The decision is made centrally in Canada, but the visa is placed into your passport locally.
They say, 13 days for the NYC, 14 days for China. Unless there is a very significant speed-up, IMO, this does not count either the time to mail the application, or the actual decision making time.
Total expenses were:
- visa fee
- express mail to the visa processing center
- express mail prepaid envelope
- time/money spend collecting all the necessary documents
For them, way less than $700