11. The frequency of a musical note, measured in hertz (Hz), is called its pitch. The pitches of the A keys
on a piano change exponentially, as shown.
A,
A,
55 H7
A2
110 Hz
A4
440 Hz
220 Hz
What is the frequency of Az?
(A) 880 Hz
(C) 3520 Hz
(B)
(D)
1760 Hz
7040 Hz

Arepresentative from plan 1 wants to use the graph below to sell health plans for his company. how might the graph be redrawn to emphasize the difference between the cost per doctor visit for each of the three plans? the scale on the y-axis could be changed to 0–100. the scale on the y-axis could be changed to 25–40. the interval of the y-axis could be changed to count by 5s. the interval of the y-axis could be changed to count by 20s.