If you adopt a illustration style that is quite similar to someone, example same hairstyle to the original one, but with different eyes and face features, does it consider a form of copyright infrigement?

I am adopting a disney style of drawing, and i am wondering if i am in copyright infringement?

I want to make sure if it is correct thing to do?

Hi,

I am a newbie and i am currently in the midst of building my portfolio.

I hope some veterans here might give me some advise on what sizes to save for raster jpeg illustration.

Due to the pricing issues like fotolia (vector are cheaper than jpeg), i would like to sell jpeg on sites with low pricing.

Do i really need to save files like 4000 x 4000pixels with exactly 300 dpi as shown in the fotolia and dreamtimes search gallery?

Can i just save them in 4000 x 4000 pixels with 72 dpi, and let the staffs convert for me when I submit the design files to them?

One last question is : Does shutterstock accept jpeg illustration especially for items that are isolated?

Any advises and helps are welcome. Thank you.