Answer
See the answer below.
Work Step by Step
a) The effective nuclear charge increases along the period.
b) Ionization energy increases along the period because it's harder to remove an electron strongly attracted to the nucleus.
The negative of the electron attachment enthalpy increases along the group because it's easier to add an electron that's more attracted to the nucleus than repelled by the others.
c) Be has a semi-stable filled 2s orbital as its valence, and breaking this state requires more energy than achieving it, for B, or achieving a noble gas configuration, like in Li.
