When we hold a weight at arm’s length at the height of our shoulder, the deltoid muscle is largely responsible for keeping our arm and the object at their fixed height. to estimate the tension in the deltoid, we model the arm as in the drawing below, with all forces acting on the arm at the indicated distances from the origin (o). the arm’s mass is 10 kg and its weight �⃗ ( acts on the center of gravity (cg), while the small object’s mass is 6 kg, and it exerts a force �⃗*→, all the way at the end of the arm. � = 15°

speed of light in vacuum is 300,000 km/s

speed of light in other mediums is given by the expression v = c/n, where c is the speed of light in vacuum and n is the refractive index of medium.

for the first medium v = 200,000 km/s

  so, refractive index of medium = 300000/200000 = 1.5

    1.5 refractive index is usually for glass. so first medium is glass.

for the second medium v = 250,00 km/s

so, refractive index of medium = 300000/250000 = 1.2

    1.2 refractive index is usually for water. so second medium is water.

for the third medium v = 0 km/s

so, refractive index of medium = 300000/0 = ∞

    ∞ refractive index is usually for opaque mediums. so third medium is opaque medium.

get the total number of pieces of fruit and divide it by 4 to get the average. the result is the answer to the problem. 14 total number of fruits and there are 4 members. 14 divided by 4 is equals to 3.5.