Answer
The amplitude is 6 cm
$f = 1.7~Hz$
$\lambda = 1.2~m$
Work Step by Step
The point x = 0 m oscillates between -6 cm and 6 cm. Therefore, the amplitude is 6 cm.
The wave completes one oscillation in 0.6 seconds. Therefore, the period $T = 0.6~s$. We can find the frequency as:
$f = \frac{1}{T}$
$f = \frac{1}{0.6~s}$
$f = 1.7~Hz$
We can find the wavelength as:
$\lambda = \frac{v}{f}$
$\lambda = \frac{2.0~m/s}{1.7~Hz}$
$\lambda = 1.2~m$