<span>The California current on the west coast which runs from north to south and the Gulf Stream on the East coast which runs from south to north.</span>
Explanation:
Given that,
Mass of the object, m = 7.11 kg
Spring constant of the spring, k = 61.6 N/m
Speed of the observer, 
We need to find the time period of oscillation observed by the observed. The time period of oscillation is given by :

Time period of oscillation measured by the observer is :

So, the time period of oscillation measured by the observer is 5.79 seconds.
The period will be the same if the amplitude of the motion is increased to 2a
What is an Amplitude?
Amplitude refers to the maximum extent of a vibration or oscillation, measured from the position of equilibrium.
Here,
mass m is attached to the spring.
mass attached = m
time period = t
We know that,
The time period for the spring is calculated with the equation:

Where k is the spring constant
Now if the amplitude is doubled, it means that the distance from the equilibrium position to the displacement is doubled.
From the equation, we can say,
Time period of the spring is independent of the amplitude.
Hence,
Increasing the amplitude does not affect the period of the mass and spring system.
Learn more about time period here:
<u>brainly.com/question/13834772</u>
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