<u>Answer:</u>
<em>Anytime observations need to be clarified. When an unusual condition need to be shown for later reference.</em>
<u>Explanation:</u>
Instead of just recording the data the is sometimes important to be sketched out as the data observed is needed to be clarified and also sometimes there is an unusual condition that occurs and hence, it is important to sketch it so that it can be used for later reference.
<em>Therefore, when we are aware of the situation we need not sketch the data.</em>
Answer:
tightly packed group of older stars
large grouping of more than two stars
loose, disorganized star cluster held together by gravity
Answer:
Erosion, weathering
Explanation:
Earth changes in its own natural ways. Some changes are due to slow processes, such as erosion and weathering, and some changes are due to rapid processes, such as landslides, volcanic eruptions, Tsunamis and earthquakes.