Answer:
Negative acceleration occurs when the acceleration vector points to the left.
1. Object slowing down in the positive direction.
2. Object speeding up in the negative direction.
Following six statements:
1. T
2. F
3. T
4. T
5. F
6. T
Check direction of acceleration vector.
To develop this problem it is necessary to apply the concepts related to Gravitational Potential Energy.
Gravitational potential energy can be defined as

As M=m, then

Where,
m = Mass
G =Gravitational Universal Constant
R = Distance /Radius
PART A) As half its initial value is u'=2u, then



Therefore replacing we have that,

Re-arrange to find v,



Therefore the velocity when the separation has decreased to one-half its initial value is 816m/s
PART B) With a final separation distance of 2r, we have that

Therefore




Therefore the velocity when they are about to collide is 
Answer:
glass if for a good view, but for absorbing heat concrete and brick is the best
Explanation:
wood is not a good idea bc it can cause fires from too much heat and it absorbs less heat but all of that depends on how good the material your using
The best and most correct answer among the choices provided by your question is the fourth option or letter D. Trade winds blow towards the equator because t<span>he Equator receives the most heat energy.
</span>The surface air that flows from these subtropical high-pressure belts toward the Equator is deflected toward the west in both hemispheres by the Coriolis effect. These winds blow<span> predominantly from the northeast in the Northern Hemisphere and from the southeast in the Southern Hemisphere.
I hope my answer has come to your help. Thank you for posting your question here in Brainly.
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