Answer 1

C can be slightly faster than C++ when you are using templates / virtual functions, other than that not that much. Fortran can also be faster than C++ when doing heavy scientific computations. But the absolute fastest can be small portions of hand written Assembly for the native architecture.

Performance really mostly boils down to the programmer in most cases. Using efficient algorithms, being CPU cache aware, and smart programming in general will make the biggest performance impacts.

Answer 2

after? you should ask before like, e.g., c, since cpp ain't the fastest.