Answer:
So mass of the object will be 3.2 kg
Explanation:
We have net force on the object F = 16 N
Acceleration of the object 
We have top find the mass of the object
From newton law of motion we know that force is given by
F = ma , here m is mass and a is acceleration
So 

So mass of the object will be 3.2 kg
During its lifepsan, the sun's core would keep contracting and heating up.
The temperature will keep increasing to the point where the temperature outside the core will get to hydrogen fusion temperatures.
The sun will grow in surface and eventually became the Red Giant
<span>They are used to measure and map effluent and pollution discharges from factories and sewerage plants, and the movement of sand around harbours, rivers and bays. Radioactive materials used for such purposes have short half-lives and decay to background levels within days.</span>
Answer:
Due to Conservation of Energy just as the ball hits the ground it's potential energy is assumed zero
Therefore disregarding air resistance all energy is converted into potential energy.
So KE = PE
(5 J)
A heat engine would be less efficient due to many factors
For instance, a heat engine is more efficient when it uses in cold weather because there is a greater temperature difference ( Carnot Efficient )
A heat engine could be less efficient because of friction
Hope it helps I am a beginner