Answer:
v_average = 15 m / s
Explanation:
The average speed can be found in two ways,
* taking the distance traveled and divide it by the time spent
* taking the velocities in each time interval and then finding the weighted average by the time fraction
v_average = 1 / t_total ∑ 
vi ti
Let's apply this last equation
Total time is
t = t₁ + t₂
t = 10 + 10 = 20 min
v_average = 10/20 10 + 10/20 20
v_average = 10/2 + 20/2
v_average = 15 m / s
Langerhans cells exist on the surface of the skin. They help to protect you by keeping dangerous microbes from entering your body. Langerhans cells do this in two very different ways: by protecting your skin from infection and also by stimulating allergic reactions.
We can answer the problem by Snell's Law:
Snell's law<span> (also known as </span>Snell<span>–Descartes </span>law<span> and the </span>law<span> of refraction) is a formula used to describe the relationship between the angles of incidence and refraction, when referring to light or other waves passing through a boundary between two different isotropic media, such as water, glass, or air.</span>
Scalar is a quantity such as mass or length that is completely determined by its own magnitude and has no direction. Therefore, your answer is Speed.
