A dolphin jumps out of the water and then back into the water. His
jump could be graphed on a set of axes where x represents time and
y represents distance above or below sea level. The domain for this
graph is best represented using a set of
(1) integers (3) real numbers
(2) positive integers (4) positive real numbers

9514 1404 393

  (4) positive real numbers

Step-by-step explanation:

The x-axis on this graph represents time. We usually are not interested in describing events before the "beginning of time," so time is generally a positive value. The domain is the description of the x-values for which the function is defined. Here, the domain is best represented by ...

  positive real numbers

rx and sx

step-by-step explanation: