Licensing for using Dash

Hi Plotly official guys,

I am using Dash to build analytical web page.
But I would like to use it as commercial use. Maybe I want to resell to others…
Can you help to answer below questions? Thanks

Q1. Do I need to buy license for commercial use?
Q2. If I sell my solution by using Dash, do I need to buy the license?
Q3. I read some articles, it seems the licensing is just to use the plotly cloud service. If I use it in my own infrastructure, do I need the license?

It uses the open source MIT licensing.
See this thread for further information: