Very powerful microscopes were needed before cells could be observed in detail
The answer is B) <span>Nuclear power has far less environmental impact than using coal or natural gas to produce electricity.</span>
Assuming its "resting" is the place in the middle of the wave crest and trough, the distance between the crest and the middle line would be considered its amplitude. The height of a wave is the distance between the crest and the trough, and wavelength is the distance between two crests.
Answer:
D. By diffusion across a capillary wall
Explanation:
D is the best answer because gas exchange takes place in our lungs. Our lungs have alveoli which have a network of tiny blood vessels called capillaries, here the O2 diffuses the capillary wall to enter the bloodstream, and similarly CO2 diffuses out and we exhale it our from our lungs.
Cells in onion peels are dead and the ones in spinach are alive.
