both the same size. 5T is older model, and 10 fps, I tried it in Best Buy, it's amazing fast, like a machine gun. 25000 iso but only 16.1 mp. A5000 is newer model. only have 16000 iso and 4fps. I bought A5000 because 20.1 mp and newer version and has flash. If you shoot sport a lot, then 5t is better. This is the image of A5000 https://www.flickr.com/photos/2009seasons/14501884263/.
Yes, you can use a telephoto lenses on this camera as long as it is an E-mount type of lens like the SEL70200G. However, if you intended to use an A-mount type like the SAL70400G2 or SAL300F28G2, you are required to use an adapter (A-mount to E-mount). Model of the adapter is LAEA4. Hope this helps. -Ely
It actually screws into the middle of the lens. On mine, I remove the lens cover, screw in the UV filter and the lends cover screws into that. I leave my UV filter on and my lends covers just snaps on and off to that just like it did with the original lens
I usually keep it on the Intelligent Auto section as it tends to adapt to the settings around you and adjusts the way it takes a picture. I also have been playing around with the different settings, but keep it on Intelligent Auto. I hope that helps you!