
Frequency, f, is how many cycles of an oscillation occur per second and is measured in cycles per second or hertz (Hz). The period of a wave, T, is the amount of time it takes a wave to vibrate one full cycle. These two terms are inversely proportional to each other: f = 1/T and T = 1/f.

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Answer:
4.61 seconds
Explanation:
Given data
Initial velocity= 12m/s
acceleration= -2.6m/s^2
From the given data
we can find the time t
we know that
Acceleration= velocity/time
time= velocity/acceleration
time= 12/2.6
time= 4.61 seconds