B. Is a single layer of flattened cells
Sleep<span> plays an </span>important role<span> in your physical health. For example, </span>sleep<span> is involved in healing and repair of your heart and blood vessels. Ongoing </span>sleep<span> deficiency is linked to an increased risk of heart disease, kidney disease, high blood pressure, diabetes, and stroke</span>
<span>A catastrophe is an event causing great and sudden damage and suffering/ a disaster</span><span />
