Canon of the canons and the scientific method, psychology homework help

1. Explain
how each canon of the canons of the scientific method is used in scientific
research. Briefly around 100-200 word will be good.

2. Provide
your own example of a study that would be low in external validity; explain why
it would be low in external validity

3. Imagine
a friend comes to you excited about a new product, the Weight-B-Gone 2000 that promises to “blast away the pounds.”  It’s been endorsed by a celebrity doctor and
uses a “cutting edge formula” to “melt unsightly fat in just minutes.”  Your friend shows you an amazing set of
before-and-after pictures of a woman who, according to the advertisement, lost
40 pounds in just 4 weeks by using the product. 
Because you are educated in research methodology, your friend asks you for advice.  Write your reply to your friend below, giving
specific evidence from the Weight-B-Gone

No plagiarism and need one reference each question and each question should be answered in about 100-200 words