1. The sp3 hybrid functions shown here
are not all possible combinations
(8 combinations are possible).
Do the others exist?
(A) No, because they are not allowed.
(B) Yes, but they are identical to the others
and therefore not shown.
(C) Yes, but they are the result of a symmetry
inversion on the C atom and the physics is
just the same.
(D) No, they would all point in the same direction,
which makes no chemical sense.

2. The sp3 hybrid functions shown here
are not all possible combinations
(8 combinations are possible).
Do the others exist?
(A) No, because they are not allowed.
Baloney!
(B) Yes, but they are identical to the others
and therefore not shown.
Not identical! See (C)
(C) Yes, but they are the result of a symmetry
inversion on the C atom and the physics is
just the same.
(D) No, they would all point in the same direction,
which makes no chemical sense.

3. How do I get experimental information on bond lengths in simple
Molecules?
(A) Vibrational spectra
(B) UV/vis spectra
(C) Microwave spectra
(D) Fluorescence spectra

4. How do I get experimental information on bond lengths in simple
Molecules?
(A) Vibrational spectra … No. I mostly get force constants here.
(B) UV/vis spectra … No. Electronic spectra carry little direct structural information.
(C) Microwave spectra … YES! Rotational constants carry bond length information!
(D) Fluorescence spectra … No. Just another form of electronic spectrum.