a. The period of the child's motion is 3.171 seconds.
b. The frequency of the vibration is 0.315 Hz.
Since A child swings with a small amplitude on a playground with a 2.5m long chain.
a. So here the time period should be
[tex]2\times \ pi(L/g)^{1/2}\\\\2\times 3.14(2.5/9.81)^{1/2}[/tex]
T=3.171s
b) Now the frequency is
[tex]T=1\div f\\\\f=1\div 3.171[/tex]
f=0.315Hz
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