188- The velocity-time graph of a simple harmonic oscillator is shown below. In the time interval $t_1$ to $t_2$, the average velocity of the oscillator is how many centimeters per second?
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[Figure: velocity-time graph of a simple harmonic oscillator, with $V$ axis in $\text{Cm/s}$, showing amplitude $10\pi$ and $-5\pi$, with time points $t_1$ and $t_2$ marked] \end{minipage} \begin{minipage}{0.45\textwidth}
- [(1)] $2/5\sqrt{3}$
- [(2)] $2/5\pi$
- [(3)] $7/5\pi$
- [(4)] $7/5\sqrt{3}$
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