The properties of the wave don't determine its speed. The properties of the medium do. You can FIND the speed by measuring the wave's frequency and wavelength.
Answer:
9] V = D ÷ T
Take any distance value from the graph and its relevant time.
V = 4 ÷ 2
V = 2 m/s
[You will notice that any distance values with its time will give you 2 m/s as its speed. This means that speed is constant throughout.]
10] Take the distance value and its time for the highest peak of B.
V = 20 ÷ 2
V = 10 m/s