Answer:

Explanation:
We first identify the elements of this simple harmonic motion:
The amplitude A is 8.8cm, because it's the maximum distance the mass can go away from the equilibrium point. In meters, it is equivalent to 0.088m.
The angular frequency ω can be calculated with the formula:

Where k is the spring constant and m is the mass of the particle.
Now, since the spring starts stretched at its maximum, the appropriate function to use is the positive cosine in the equation of simple harmonic motion:

Finally, the equation of the motion of the system is:
or

2m/s
Explanation:
Given parameters:
Distance traveled = 60m
time taken = 30seconds
Unknown:
Speed of skateboarder = ?
Solution:
Speed is the rate of change of distance with time taken. It is a scalar quantity that only revers magnitude;
Speed = 
Speed =
= 2m/s
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Speed brainly.com/question/1548911
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Hi there,
Unlike velocity,speed is scalar,which means it is described by MAGNITUDE only.