Why is this question stumping everyone i meet.

Which expression is equivalent to 4 square root 6 divided by 3 root 2

Bob the builder is making 480kg of cement mix. this is made by cement, sand and gravel in the ratio 1: 3: 4

Two poles, ab and ed, are fixed to the ground with the of ropes ac and ec, as shown: what is the approximate distance, in feet, between the two poles? 6.93 feet 8.66 feet 12.32 feet 15.59 feet