Answer:
unless acted upon by an unbalanced force.
Explanation:
If a ball is rolling, it will continue to roll forever, unless it is acted upon by an unbalanced force. For example, the friction of the floor it's rolling on slows it down. The density of the air hitting it also slows it down.
The mass of the horse is 186 kg.
The weight of the horse is
(186 kg)*(9.8 m/s^2) = 1822.8 N
According to Newton's 3rd Law, there is an equal and opposite force between the horse and the surface.
Therefore the normal reactive force is 1822.8 N.
Answer: 1822.8 N
the answer is c: kilogram
explanation: The standard International System of Units (SI) unit of mass is the kilogram (kg). The kilogram is 1000 grams (g), first defined in 1795 as one cubic decimeter of water at the melting point of ice.
Answer: The hierarchical formation model suggests that galaxies may have been formed by subsequent mergers of smaller galaxies and that today each galaxy houses at least a supermassive black hole.
Explanation: During a fusion of galaxies, the stars that composes it suffer the tidal force, intensifying your action as the galaxies approaching. When two galaxies merges themselves, the astronomers believes that they loss a huge part of their mass, forming the supremassive black hole, that stays in the middle of the galaxie.
The supermassive black holes are originated from the evolution of high mass stars. They were formed by huge clouds of gas or clusters of millions of stars that collapsed on their own gravity when the universe was still much younger and denser.
Answer:

is time required to heat to boiling point form initial temperature.
Explanation:
Given:
initial temperature of water, 
time taken to vapourize half a liter of water, 
desity of water, 
So, the givne mass of water, 
enthalpy of vaporization of water, 
specific heat of water, 
Amount of heat required to raise the temperature of given water mass to 100°C:



Now the amount of heat required to vaporize 0.5 kg of water:

where:
mass of water vaporized due to boiling


Now the power rating of the boiler:



Now the time required to heat to boiling point form initial temperature:

