Answer:
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.
People believed that zebras were white animals with black stripes, since some zebras have white underbellies. Embryological evidence, however, shows that the animal's background color is black and the white stripes and bellies are additions.
The correct answer is a.
Even-aged practices remove larger groups of trees than uneven-aged management practices. Uneven-aged management is termed as the forest management whereby trees of different species are maintained for many sizes and ages to allow continuation of natural regeneration.