FInd the acceleration of mass A of the system? Find the time it takes for Mass B to fall a height of 80 cm? Find the speed of mass B at 80cm?

acceleration a =Mb*g/(Ma+Mb) = 0,400*g/0,600 = 2g/3 m/sec^2 (≅  6.538)

falling time t = √2h/a = √1.6*1.5/g = √ 2.4/9.807 = 0.495 sec 

final speed V = a*t = 6.538*0.495 = 3.234 m/sec

or 

Mb*g*h = (Mb+Ma)/2*V^2

0.32*9,807 = 0.3*V^2

V = √0.32*9.807 / 0.3 = 3.234 m/sec 

Force of gravity = g * 0.4 kg

total mass of system = 0.6 kg

a = g * 0.4 kg / 0.6 kg