S.G. or specific gravity is the ratio of the density of an object to a fluid. It also is the fraction of the object's volume that would be submerged if the object were placed in the fluid. (note: if S.G.>1, the object will sink)
S.G. = density(wood) / density(water)
2/3 = density(wood) / 1000
density(wood) = 2000/3 kg/m^3 = ~666.67 kg/m^3
S.G. = density(wood) / density(oil)
9/10 = 2000/3 / density(oil)
density(oil) = 2000/3 / 9/10 = 20000/27 kg/m^3 = ~740.74 kg/m^3
Any of the above depending on the direction of forces
According to the Law of Conservation of Charge, the net
charge remains constant. If both things have different charges, upon contact,
they would share the charge equally. In this case, the total charge is -16μC.
The final charge for each ball would be -8 μC.
Answer:

Explanation:
Let assume that gases inside bulbs behave as an ideal gas and have the same temperature. Then, conditions of gases before and after valve opened are now modelled:
Bulb A (2 L, 2 atm) - Before opening:

Bulb B (3 L, 4 atm) - Before opening:

Bulbs A & B (5 L) - After opening:

After some algebraic manipulation, a formula for final pressure is derived:

And final pressure is obtained:

