Answer
See the answer below.
Work Step by Step
a) Angle 1: 109°, bent geometry from the tetrahedral archetype (2 ligands, two lone pairs)
Angles 2 and 3: 120°, trigonal planar geometry (3 ligands, no lone pairs)
Angle 4: 109°, trigonal pyramidal geometry from the tetrahedral archetype (3 ligands, one lone pair)
Angle 5: 109°, tetrahedral geometry (4 ligands, no lone pairs).
b) The O-H bonds because they have the biggest difference in electronegativity between the ligands.
