Answer:
The approximate frequency of the signal is 12 Hertz
Explanation:
Frequency is defined as the number of complete cycles that passes a given point in a given time
One cycle is the motion that describes one complete rotation, such that one cycle is described by the region between successive crest or peaks
Therefore, we have from the diagram;
The number of cycles in 0.75 seconds ≈ 9 cycles
The number of cycles expected to pass in one second = 9 cycles/(0.75 seconds) = 12 cycles/second = 12 Hertz
The approximate frequency of the signal, f = 12 cycles/second = 12 Hertz.