Please post in English so i or someone else can help you.
The two situations are similar because in both you are trying to minimize the damage and make the best out of a bad situation
Answer:
Resistance = 3.35*
Ω
Explanation:
Since resistance R = ρ
whereas 
resistivity is given for two ends. At the left end resistivity is
whereas x at the left end will be 0 as distance is zero. Thus

At the right end x will be equal to the length of the rod, so 
Thus resistance will be R = ρ
where A = π 
so,

Answer:
There would be a pressure drop in the direction of the higher opening. This will force air to move in from the lower opening and force it to leave through the higher opening. This will create a convectional movement of air, cooling and ventilating the tunnel.
Explanation:
This is in accordance with bernoulli's law of fluid flow which states that the pressure exerted by a moving fluid is lesser than it would exert if it were at rest.
Answer:
height of the water rise in tank is 10ft
Explanation:
Apply the bernoulli's equation between the reservoir surface (1) and siphon exit (2)

-------(1)
substitute 
0ft/s for V₁, 20ft for (z₁ - z₂) and 32.2ft/s² for g in eqn (1)


Applying bernoulli's equation between tank surface (3) and orifice exit (4)

substitute

0ft/s for V₃, h for z₃, 0ft for z₄, 32,2ft/s² for g

At equillibrium Fow rate at point 2 is equal to flow rate at point 4
Q₂ = Q₄
A₂V₂ = A₃V₃
The diameter of the orifice and the siphon are equal , hence there area should be the same
substitute A₂ for A₃
for V₂
for V₄
A₂V₂ = A₃V₃

Therefore ,height of the water rise in tank is 10ft