What is the difference between "Lechem Matzos" and "Chalos Matzos"?
The Gemara in Menachos (78b) calls them 'Revuchah' (scalded) - which it learns from the Chavitei Kohen Gadol (See Sifsei Chachamim). The three types of Matzah mentioned here are synonymous with the three kinds mentioned in Vayikra 8:26 (Rashbam). 2
They were also baked in an oven (Rashbam - See also Sifsei Chachamim).
What is the difference between "Belulos ba'Shemen (in connection with the Chalos) and "Meshuchim ba'Shemen" (in connection with the wafers)?
Rashi: They poured oil into the former and mixed it whilst it was still flour (before baking it), whereas they smeared oil on to the latter 1 after they were baked.
In the form of the Greek letter 'Xi', which resembles an X (Menachos, 4b).
What did they do with the left-over oil?
Sifsei Chachamim: According to one opinion, it was given to the Kohanim to 'eat'; according to others, they continued smearing it on the oil was finished.
The Torah does not state how many loaves of each kind of Matzos there were?
Rashi: Each of the three kinds of Matzah comprised ten loaves. 1
Which the Gemara in Menachos 76a, learns from the Lachmei Todah (See Sifsei Chachamim).
What species of grain was used to make the various kinds of Matzah?