Domain and range of the function

Identify the number as a rational or irrational.explain. 127

Ef is a median of trapezoid abcd. the length of ab is 12, and the length of cd is 18. the length of bf is 4. what is the length of fc?

There are 1872 steps in a building that has 104 floors. each floor has the same number of steps. a second building has the same number of floors but 2 fewer steps between each floor. how many steps are there between each floor of the second building?