1)
What is "Ma'ug"?
1.
Rashi: It is like a cake.
2.
Radak: It is anything round, be it a big or small piece.
2)
What is "Melo Chaf"?
1.
Rashi citing Targum Yonasan: It is enough to fill the palm.
3)
What is the significance that Eliyahu came when she had so little remaining?
1.
Malbim: Hashem does a miracle only when there is a great need. As long as she had enough for a meal, He would not miraculously increase the flour and oil.
4)
Why did she say "va'Masnu"?
1.
Rashi: After this, we will die of hunger.