The cost function is $\"\"$ , where $\"\"$ is the number of minutes used.

(a)

The parent function is greatest integer function $\"\"$ .

The graph of $\"\"$ is the graph of $\"\"$ compressed vertically and translated $\"\"$ units up.

(b)

Write the function $\"\"$ to decribe the second plan.

Daily access rate is $\"\"$ , and per-minute rate is $\"\"$ .

The cost function is $\"\"$ .

(c) Graph the two functions $\"\"$ and $\"\"$ on same axes.

$\"\"$

(d)

Observe the graph: The cost functions $\"\"$ and $\"\"$ equal to each other.

The plans will equal to each other at $\"\"$ minutes.

(a) The graph of $\"\"$ is the graph of $\"\"$ compressed vertically and translated $\"\"$ units up.

(b) The cost function is $\"\"$ .

(c) Graph of the two functions $\"\"$ and $\"\"$ on same axes.

$\"\"$

(d) Yes; the plans will equal to each other at $\"\"$ minutes.