<h2>
Answer: Gravity force</h2>
If we approximate the orbit of the planets around the Sun to circular orbits with a uniform circular motion, where the velocity 
is a vector, whose direction is perpendicular to the radius 
of the trajectory; the acceleration 
is directed towards the center of the circumference (that's why it's called centripetal acceleration).
Now, according to Newton's 2nd law, the force 
is directly proportional and in the same direction as the acceleration:
Therefore the net force resulting from the movement of a planet orbiting the Sun points towards the center of the circle, this is called Centripetal Force which is a central force that in this case is equal to the gravity force.
I think its true, I think.
Answer:
A) exothermic, δh is negative
B) endothermic, δh is positive
C) endothermic, δh is positive
Explanation:
And endothermic process absorbs heat from its sorrounding, cooling the sorrounding down. Whereas an exothermic process releases heat to its sorrounding raising the temperature of the sorrounding system.
-- Looking at the dots casually, they look green because they absorb all other
colors of light, and only green light is left to proceed to your eyes. (In order for
this to work, there has to be some green in the light shining on the dots.
Daylight and most light bulbs work fine.)
-- The filter looks red because it absorbs all other colors of light, and only
the red light is left to pass through the filter and come out on the other side.
-- When the green light from the dots hits the red filter, it's absorbed in the
filter, and there's no light left to come out on the other side.
If you're looking through the filter at the dots, they look <em>black</em>.
