Answer:
option B
Explanation:
When a body is immersed in liquid there will be two force is acting on the body.
First one force acting downward due to weight of the body.
And the second force acting on the object will be buoyant force.
If the object is not in equilibrium the apparent weight will be equal to net force acting on the object.

W is the weight of the object acting downward
Fb is the buoyancy force acting upward on the object.
Hence, the correct answer is option B
Answer:
a)= 0.025602u
b) = 23.848MeV
c) N = 1.546 × 10¹³
Explanation:
The reaction is
²₁H + ²₁H ⇄ ⁴₂H + Q
a) The mass difference is
Δm = 2m(²₁H) - m (⁴₂H)
= 2(2.014102u) - 4.002602u
= 0.025602u
b) Use the Einstein mass energy relation ship
The enegy release is the mass difference times 931.5MeV/U
E = (0.025602) (931.5)
= 23.848MeV
c)
the number of reaction need per seconds is
N = Q/E
= 59W/ 23.848MeV

N = 1.546 × 10¹³
Answer:
a. burning of fossil fuel
Explanation:
Greenhouse effect is the trapping of the sun infrared rays in the outermost layer of the earths atmosphere due to the accumulation of some harmful gasses. This gases depletes the ozone layer
The major contributor of greenhouse gases is the burning of fossil fuels. Carbon dioxides are released into the atmosphere and leads to global warming and climatic changes per time
Answer : 2446 years.
Explanation :
Length of semi major axis is, 
According to Kepler's third law, square of time period of an orbit is directly proportional to the cube of the semi major axis.
i.e 
where G is gravitational constant
M is mass of sun, 
So, 




since, 
So, orbital period is approximately 2446 years.
You would know a decomposition reaction occurred if the reactants separated. For example from AB → A+B.
Now if you look at your options only 1 works out for that equation. Letter A.
From the compound K2CO3 it split up to K2O +CO2
It cannot be letter B because synthesis/combination occurred. The same goes for letter C. Letter D, single displacement occurred.
Again, the answer is A.