Answer: Hydrosphere, discontinuous layer of water at or near Earth's surface. It includes all liquid and frozen surface waters, groundwater held in soil and rock, and atmospheric water vapour. Earth's environmental spheresEarth's environment includes the atmosphere, the hydrosphere, the lithosphere, and the biosphere.
Explanation:
Answer:
The melting point of a substance is the temperature at which it change state from solid to liquid is called crystallization point.
Answer:
english:
Solid is the state in which matter maintains a certain volume and shape; liquid is the state in which matter conforms to the shape of its container, but varies only slightly in volume; gas is the state in which matter expands to fill the volume and shape of its container.
español:
Sólido es el estado en el que la materia mantiene cierto volumen y forma; el líquido es el estado en el que la materia se adapta a la forma de su recipiente, pero varía sólo ligeramente en volumen; el gas es el estado en el que la materia se expande para ocupar el volumen y la forma de su recipiente.
Answer : The time passed in years is 
Explanation :
Half-life of carbon-14 = 5730 years
First we have to calculate the rate constant, we use the formula :



Now we have to calculate the time passed.
Expression for rate law for first order kinetics is given by:

where,
k = rate constant = 
t = time passed by the sample = ?
a = initial amount of the reactant disintegrate = 15.3
a - x = amount left after decay process = 14.8
Now put all the given values in above equation, we get


Therefore, the time passed in years is 
817.567 mm hg the answer for number 2