Answer from cs61c-ec (Osbert Orr 16671538) for Question 4
For IEEE 754 would be that it is a widely implemented standard with a common floating-point format, it requires minimum accuracy to one-half ulp in the least significant bit, and that uperations must be commutative.

Against IEEE 754 would be that the community has been slow to make IEEE 754's unusual features available to the applications programmer such as directed rounding.