Answer:
The law of conservation of mass or principle of mass conservation
Explanation:
It states that for any system closed to all transfers of matter and energy, the mass of the system must remain constant over time, as the system's mass cannot change, so quantity can neither be added nor be removed.
The nebular hypothesis is the name of the theory where gravitational attraction caused bits of matter to collapse, eventually forming a solar system.
Hope this helps :)
'C' is a simple explanation of astigmatism.
Answer:
The slope of a position-time graph can be calculated as:
where
is the increment in the y-variable
is the increment in the x-variable
We can verify that the slope of this graph is actually equal to the velocity. In fact:
corresponds to the change in position, so it is the displacement, 
corresponds to the change in time 
, so the time interval
Therefore the slope of the graph is equal to
which corresponds to the definition of velocity.
The situation is impossible mainly because we can't see Figure P6.10 .
It would undoubtedly be the same story on an another planet, until we
see the figure and understand what's going on.
