Ferns<span>, </span>horsetails<span>, </span>mosses<span>, and </span><span>liverworts, flowers, mint</span>
Answer:
D: 4.6 x 
Explanation:
4.6 x 10^{9} = 4,600,000,000
Earth is approximately, 4.6 billion = 4,600,000,000 = 4.6 x 10^{9}
<span>The correct answer is b.0.5 to 1 micrometre thick.</span>
Usually, the respiratory membrane is about 0.6 micrometres thick. This membrane consists of the alveolar epithelial cells, the capillary endothelial cell, and basement membranes which are formed by the alveolar and capillary cells.
<span>Cenozoic
</span><span>Mesozoic
</span><span>Paleozoic
</span><span>Precambrian </span>
The answer is a cellular membrane
