Multiple work experiences and multiple NOC category

Hi All,

I want to apply for express entry and want to show 3 years of experience with different NOC A Category codes. Following is my whole history:

  1. B.Tech Biomedical Engineering
  2. I worked for a year at a local firm with NOC 1122 or 2141. I am confused as I worked as Quality Engineer and not sure which one should I use. Please suggest.
  3. Then I started my Master in Biomedical Engineering in US.
  4. While doing my masters in US I worked as Research Assistant (Research fellow - NOC 4012 or should I use Biomedical engineering - 2148) for 1 year and 1 month which I feel I can use (https://www.cic.gc.ca/english/helpcentre/answer.asp?qnum=394&top=6). Please advise.
  5. Then I worked full time for three months as NOC 1122.
  6. Graduated.
  7. Then I worked in multiple companies with same titles falling in NOC 1122 for small duration (all full time) as described below:
    i. 2019 Jun to Oct - 3 months
    ii. gap of 2 months
    iii. 2019 Dec to 2020 Oct - 10 months
    iv. 2020 Oct to present - 2.5 months.

Can anyone suggest me would I be able to show three years of work experience with such profile?
Your valuable guidance is highly appreciated. Many thanks in advance.