US citizen applying for spouse PR - US/CAN border crossing ????

[CanUs]

Hi, I'm in need of some good info and am very grateful to anyone that can give me some insight to our unique situation.....

My husband and I just moved back up to the Washingon / BC area. I am a US citizen my current residence is in northern Washington. My husband, Canadian citizen, (to be my sponsor) and his family live in near the border in BC.
Currently, I have a part-time job in a US border town, I just got hired and don't plan on quitting any time soon. The commute is very reasonable and I need to make some $ to help us out, since I can not work in Canada. My husband works in BC.

my Purpose of PR in Canada is to
- live (legally) with my husband
-study Nursing at University, eventually work in that field
-possibly start a family, etc.

????'s
1. While applying for PR status (in Canada) can I continue to cross the border (probably about 2-3 times a week) using my US passport?
2. When crossing is it safe to say that I am working in US but am in the application process for my PR in BC?
3. Can I keep my job during the application process and after I get PR status- since I intend on living in BC, paying taxes, studying, etc.?

thanks