Physics Question, I need help

Question

I've been having trouble with this Physics Question (the picture below) if someone may help me please.

Answer 1

(1) Well as water level increases from 200 to 224 ml, volume of displaced water = 224 - 200 = 24 ml

(2) Buoyant force = weight of water displaced. 1 l water has mass 1 kg, so mass of water displaced = (24/1000) kg. Weight = mg, so weight = (24/1000) kg, lets say g = 10 m/s/s, so 0.24 N

(3) Buoyant force = solid's weight, so weight = 0.24 N

(4) Density = mass of solid / volume. Mass = 0.024 kg. (0.24 / 10). Volume is 40 ml = 0.04 l

So density in kg/l is 0.024 / 0.04 = 0.6 kg/l

Mike