Answer:
The air pressure in the tank is 53.9 
Solution:
As per the question:
Discharge rate, Q = 20 litres/ sec = 
(Since, 1 litre =
)
Diameter of the bore, d = 6 cm = 0.06 m
Head loss due to friction, 
Height, 
Now,
The velocity in the bore is given by:


Now, using Bernoulli's eqn:
(1)
The velocity head is given by:

Now, by using energy conservation on the surface of water on the roof and that in the tank :




Answer with Explanation:
The crown will be pure if it's specific gravity is 19.3
Now by definition of specific gravity it is the ratio between the weight of an object to the weight of water of equal volume
Since it is given that the weight of the crown is 11.8 N we need to find it's volume
Now According to Archimedes principle when the crown is immersed into water the water shall exert a force in upwards direction on the crown with a magnitude equaling to weight of the water displaced by the crown
Mathematically this is the difference between the weight of the crown in air and weight when immersed in water
Thus Buoyant force is 
Now by Archimedes principle This force equals in magnitude to the weight of water of same volume as of the crown
Thus the specific gravity of the crown equals

As we see that the specific gravity of the crown material is less than that of pure gold hence we conclude that it is impure.
Answer: Contaminants can cause tremendous harm to a population; not only humans but entire local animal species can be devastated by poisonous drinking water. Crops and livestock can also be affected. Citizens can make prudent choices regarding natural resources and energy use. Scientists can research and create products that can reduce or eliminate unnecessary waste and pollution.
Explanation:
Answer: Batteries have three parts
Explanation:
Batteries have three parts, an anode , a cathode , and the electrolyte. The cathode and anode the positive and negative sides at either end of a traditional battery are hooked up to an electrical circuit. The chemical reactions in the battery causes a build up of electrons at the anode.
You connect the motherboard to the astronomical blow up device