Poindexter received a 55 on a biology test (X = 50) and a 45 on a philosophy

Question:

Poindexter received a 55 on a biology test (X = 50) and a 45 on a philosophy test (X = 50). He is considering whether to ask his two professors to curve the grades using z-scores.
(a) Does he want the SX to be large or small in biology? Why?
(b) Does he want the SX to be large or small in philosophy? Why?