21: potassium has 20 neutrons
22: is d
Answer:
=final temperature
Explanation:
In the question specific heat of water is not given but we should know the value of that and it 4.18Jg∘C
Specific heat means how much heat is required to increase the temperature of 1 gram of substance that substance by 1∘C .
Equation between heat lost or gain and the change in temperature.
q=m⋅c⋅ΔT , where
q - the amount of heat
m - the mass of the sample
c - specific heat of sample
ΔT - change in temperature
put all the given value into this ,




=final temperature.
Answer:
a number of people or things that are located close together or are considered or classed together.
Explanation:
Salt in water is Homogeneous and salt in gravel is heterogeneous <span />
Answer:
there is a distinct decrease of salinity near the equator and at both poles, although for different reasons. Near the equator, the tropics receive the most rain on a consistent basis. As a result, the fresh water falling into the ocean helps decrease the salinity of the surface water in that region.