The most suitable option for the first question is definitely <span>stratus clouds which usually stratch over the sky creating overcasts.
The next one should be </span><span>nimbus, as they dark and usually help to predict the storm.
And the last one </span>cumulonimbus that point on thunderstorms and so on.
Alkaline earth metals
Group 13 aka the boron family is categorized as alkaline earth metals
The answer is D. corals are imperative to damage
The answer is A. i say this because when they use sunlight as energy, cabon dioxide and water are converted into organic material, they are used as cellular functions ( such as biosynthesis and respiration ). An able autotroph is able to make his own food.