Tectonic plates are pieces of Earth's crust and uppermost mantle, together referred to as the lithosphere. The plates are around 100 km (62 mi) thick and consist of two principal types of material: oceanic crust (also called sima from silicon and magnesium) and continental crust (sial from silicon and aluminium)
please make me brainlist answer
Here something that might help
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Most scientists believe that for half of </span>Earth's<span> 4.6-billion-year history, the</span>atmosphere<span> contained almost no </span>oxygen<span>. Cyanobacteria or blue-green algae became the first microbes to produce </span>oxygen<span> by photosynthesis, perhaps as long ago as 3.5 billion years ago and certainly by 2.7 billion years ago.</span>
<span>Ozone intake can cause irritation to the respiratory system. It can also inhibit absorption of certain nutrients. Certain people are more at risk for example children. This is because thier lungs are still developing. They are also more likely to be outdoors and more likely than adults to have asthma. Symptoms shortness of breath and coughing.</span>
Unfortunately this question is incomplete as no options are provided. IN actual fact,<span> four muscles are involved in mastication. Three of these are responsible for biting down, namely the masseter, the temporalis and the medial pterygoid, whereas one, the lateral pterygoid, is responsible for opening of the jaw</span><span>. All four muscles help to move the jaw laterally.</span>
the is a definite article meaning that you cannot use it
"an" can only be used before words beginning with vowels
therefore the answer is" a"
