Will a wooden beam weighing 108 kg be able to hold a weight of 70 kg above water? The density of the tree is 600 kg / m3.

mb = 108 kg.
mg = 70 kg.
g = 9.8 m / s ^ 2.
ρw = 1000 kg / m ^ 3.
ρb = 600 kg / m ^ 3.
Farkh -?
2 forces act on a load with a wooden bar: gravity (mb + mg) * g and the force of Archimedes Farkh. In order for the bar to be able to hold the load, these forces must be equal: (mb + mg) * g = Farch.
(mb + mg) * g = (108 kg + 70 kg) * 9.8 m / s ^ 2 = 1744.4 N.
Farch = ρw * g * Vb, where ρw is the density of water, g is the acceleration of gravity, Vb is the volume of the submerged part of the wooden bar.
Vb = mb / ρb.
Farch = ρw * g * mb / ρb.
Farch = 1000 kg / m ^ 3 * 9.8 m / s ^ 2 * 108 kg / 600 kg / m ^ 3 = 1764 N.
We see that Farkh = 1764 N> (mb + mg) * g = 1744.4 N.
Answer: a block of wood will be able to hold the load.