(an interesting aspect of this formula is that, even though it involves taking the square root of a potentially-odd power of a potentially-negative , it cannot produce a complex result if neither  nor  has an imaginary part. an outline of this second approach is given in a separate section below. it was produced in 2,600 examples. working people could escape, for a time, their everyday world. the player still had to solve the puzzle to keep the prize. the school has a dive shop that also services other divers besides the students. 