Frequency = rate of sploosh = 2 per second = 2 Hz.
Period = ( 1/frequency ) = 1/2 second
Speed = (wavelength) x (frequency) = (0.15m) x ( 2/sec) = 0.075 m/s .
The centripetal acceleration of an object is given by the relation,

where Ac = centripetal acceleration =
R = radius of rotation = 15 m
V = speed of astronaut
Hence, 
solving this we get, V = 38.34 m/s
Answer: 5.8 m/s squared
Explanation: just got that question lol
You can calculate potential energy by:
U = m.g.h
Where, U = potential energy
m = mass
g = acceleration due to gravity
h = height
Hope this helps!