A set of numbers is said to be COMMUTATIVE under the operation '+' if m + n = n + m, for any two numbers m and n of that set. Similarly, a set of numbers is said to be COMMUTATIVE under the operation '×' if m × n = n × m. Which of the following sets is COMMUTATIVE under the operation '-'?

A)the set of integers
B)the set of natural numbers
C)the set of rational numbers
D)none of the above

Which number line correctly shows 0.8 + 0.3?

The weight of a radioactive isotope was 96 grams at the start of an experiment. after one hour, the weight of the isotope was half of its initial weight. after two hours, the weight of the isotope was half of its weight the previous hour. if this pattern continues, which of the following graphs represents the weight of the radioactive isotope over time? a. graph w b. graph x c. graph y d. graph z

To prove a polygon is a rectangle, which of the properties listed must be included in the proof?