1. How did the Cohanim wash their hands and feet?

• The Cohanim we required to wash their hands and feet at the exact same time. This was done by placing the right hand on top of the right foot and vice versa for the left side. (Ohr HaChaim, Rashi in Zevachim 19b)

2. How old was Betzalel when he built the Mishkan?

• The responsibility for the construction of the Mishkan was given by Hashem to Betzalel. He was only 13 years old at that time. (Sanhedrin 69b)

3. What special knowledge did Betzalel possess?

• Betzalel knew how to combine the sacred letters with which Hashem created the heaven and the earth. It seems that Betzalel possessed  a level of wisdom similar to the level of wisdom that Hashem used to create the universe. (Berachot 55a)

4. How were the letters inscribed on the Luchot ?

• The writing on the Luchot appeared the same way on both sides despite the fact that the letters were inscribed right through the stone. So too, the letters Samech and Mem remained suspended in mid-air. (Shabbat 104a, Ohr Hachaim)

5. How heavy were the Luchot?

• According to some sources, the Luchot were incredibly heavy. It was only due to their holiness that  Moshe was miraculously able to carry them. When Moshe saw what  was happening with the golden calf, the letters on the Luchot floated back to heaven. Once the Luchot were lacking their sanctity, the miracle ceased and Moshe could no longer carry them. At that point, he understood that they were meant to be destroyed. (Yalkut 393) According to other sources, Hashem ordered Moshe to smash them. (Avot deRabbi Nathan)