59 divided by 7 is 8 with 3 remaning but all must be included so you have anothr crate for the remaining the and sice 8+1=9. Velma needs 9 crates. Hope this Helps!!
For a glider, which a paper airplane is the more lift the glider has the longer it can fly. However, you must keep the weight and drag in check to avoid flight failure.
