Answer:
a) 3.37 x 
b) 6.42kg/
Explanation:
a) Firstly we would calculate the volume of the metal using it`s weight in air and water , after finding the weight we would find the density .
Weight of metal in air = 50N = mg implies the mass of metal is 5kg.
Now the difference of weight of the metal in air and water = upthrust acting on it = volume (metal) p (liquid) g = V (1000)(10) = 14N. So volume of metal piece = 14 x
. So density of metal = mass of metal / volume of metal = 5 / 14 x
= 3.37 x 
b) Water exerts a buoyant force to the metal which is 50−36 = 14N, which equals the weight of water displaced. The mass of water displaced is 14/10 = 1.4kg Since the density of water is 1kg/L, the volume displaced is 1.4L. Hence, we end up with 3.57kg/l. Moreover, the unknown liquid exerts a buoyant force of 9N. So the density of this liquid is 6.42kg/
The answer is carbon dioxide. This primordial earths’ atmosphere was composed by gasses from degassing of the earth's interior after its formation. It is after the beginning of life that oxygen levels began to rise and levels of carbon dioxide began to reduce in the atmosphere (as a result of photosynthesis).
Answer:
When net force of zero acting on a ball which is at rest , then the object center of mass will not accelerate , but the object may begin to rotate .
Explanation:
Here when there is an object where several forces are acing upon are zero then the center of mass will not accelerate because we know that

Where
acceleration of center of mass
= net force = 0
So the acceleration of center of mass will be zero
But the torque ,may not be zero as torque is product of individual force and perpendicular force .
Since if torque is not equal to zero then the object may begin to rotate
Dalton's <span>law of partial pressures
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