A:AnswerYes it can. The physical interface is the same - and the spee is controlled on this model by which port it is plugged into.
Below are from the specs for this 2014 product.
Includes:
Two USB 3 ports (up to 5 Gbps)
Thunderbolt port (up to 10 Gbps)
A:AnswerYes. The cable (whether USB-C or Apple thunderbolt 3) is a data transfer cable capable of file data, viseo, and music data. Data is a very broad term but the simple anser is yes.
A:AnswerDo NOT buy this for eGPU purposes. This cable is listed as Thunderbolt 2-compliant, which can very much be only half as performant (max 20Gbps) as a Thunderbolt 3 (max 40 Gbps) cable. You will want the TB 3 cable to maximize your eGPU performance.