ds -160 help needed

[need_help123]

i am filling ds -160 for canada and i need help with following question.

(1) 1) Intended length of stay in U.S.

my visa is valid from 11/19/2015 to 07/19/2018,should i put just 3 years
or do i need to count weeks from today which is not 3 years.

2) last 5 USA visit

here do i need to start from 2008 and then again i went for vacation for 3 months.
again i came back and then visit india.how should i fill this information. as i visited canada and india during my stay to USA.

(3) Previous US visa:

should i mention my previous h1 visa ? as this is my second h1b ,first h1 has expired.

(4) have you ever been issues to US visa i put here YES
now under that there is 1 question :
Are you planning in the same country or location where visa above was issued
and is this country or location your place of principal of residence what should be answer : yes/no

i am planning to go same place in canada for my second time visa stamping so it should be yes ,however its not my principal of residence.

please answer me asap

[jnk]

1. Count exact duration.
2. USA visits during Years 2011 to 2015.
3. Yes
4. It should be Yes