Confederation Navy: Spinal Mounts
Q. The mass driver short range would be against manoeuvrable spacecraft, under twelve and a half hundred klix.
R. Orbital bombardment starts off with minus twelve, short range is plus one, tempered by platform mass of at least minus one to at most minus four, since you have to wonder if there's much point in building a Death Star.
S. Under ten kilotonnes, it's basically like a howitzer with open sights; no, a mortar.
T. Likely minus eleven, plus six for six kilotonne plus target, advanced fire control fourteen plus three, so minus two; or fire control five, which would be zero (since I don't think they should stack).
U. At close range it's dogfight mode, and then it's probably over.