2. How many boards were used on the right and left sides of the Mishkan?
3. Where did Betzalel get the cedar wood used in the Mishkan?
4. Did the Aron have legs on the bottom or did it sit flat on the ground?
Answers:
1. Three (Rashi 25:11).
2. Twenty on each side (26:18, 20).
3. Yaakov Avinu saw through his Ruach HaKodesh that Klal Yisroel would need to build the Mishkan in the desert and he brought cedar trees to Egypt and planted them. He commanded his children to take them when they left Egypt (Rashi 25:5).
4. According to the Ibn Ezra (25:12), the Aron had legs because it was not respectful to allow it to rest directly on the ground.