Can you tell me what the acids/bases and conjugate acids/bases are?

hf(aq)+so42-(aq) < --> f-(aq) + hso4-(aq)

The correct answer to this question is this one:

HF (hydrofluoric acid) is a weak acid.
SO4 2- (sulfite ion) is a weak base
F- (fluoride anion) is a very weak base
HSO4 - (hydrogen sulfate) is a weak acid

Conjugate acid of HF = H2F+ (dihydrogen fluoride)
Conjugate base of HF = F- (fluoride)

Conjugate acid of SO4 2- = HSO4- (hydrogen sulfite)
SO4 2- does not have a conjugate base because you can't take away any H+

Conjugate acid of F- = HF (hydrofluoric acid)
F- does not have a conjugate base because you can't take away any H+

Conjugate acid of HSO4- = H2SO4 (sulphuric acid)
Conjugate base of HSO4- = SO4 2- (sulfite)

In very simple words:
Conjugate acid --> you add an H+
Conjugate base --> you take away an H+

Thomson is the scientist who designed an experiment that enabled the first successful detection of an individual subatomic particle. J.J. Thomson (Sir Joseph John Thomson, 1856-1940), who demonstrated in 1897 that "cathode rays" consisted of negatively-charged particles, later named electrons.