Given the following circumstances, what counting formula should be used? 1) the order of selection is important. 2) repetition is not allowed. 3) there are no identical objects. a. npr b. ncr c. fundamental counting principle d. n!

0.22hz

Step-by-step explanation:

Hi to answer this question we have to analyze the information given:

So, to calculate the frequency of the pendulum we have to apply the formula;

Frequency (f)= 1 / period  

Replacing with the value given:

f = 1/ 4.5 sec = 0.22 hz

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