I created a R markdown file on R Studio and used the Knit function to create an html file. Eventually, .md file and html files were created in my working directory. Also, a figures folder/directory was created automatically. And hence, I pushed all the changes made to my GitHub repository.
Now, my problem here is when I open the .md (markdown) file on GitHub, it doesn't view the plots. It shows the link to it though. Attached a snippet for reference.
I tried a couple of things which didn't work:
Added the below code chunk
library(knitr)
opts_chunk$set(dev="png")
Impended ?raw=true end of the image link. I changed
 to

I am using:
R-Studio Version : 1.0.143
Windows 7
Solved the problem!
I removed spaces from code chunk names and it worked.
I can now view plots/figures in the markdown file.
One of the posts on R-studio support had me try this solution. Repeated google search helped.