Plant trees on places where forests have been chopped down to restore damaged ecosystems. Encourage individuals to live in a way that is environmentally friendly. Create parks to conserve the rainforests and animals. Companies that operate in environmentally friendly methods should be supported.
Use the formula below for this question:

re-arrange to solve for a:

now simply plug in your variables and there's your answer :). If you ever get stuck, you can look up the kinematic equations!
Refraction is the change in direction of waves that occurs when waves travel from one medium to another. Refraction is always accompanied by a wavelength and speed change. Diffraction is the bending of waves around obstacles and openings.
Explanation:
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