Earth surface are composed of 70% of water and 30% of lands or soil.
Therefore, whatever happens to our earth surface results to global warming.
Trees, waters and other natures protect our mother earth from direct heat of ultraviolet rays of sunlight, when these are gone, it will result to too much heat and even damage to our environment.

Describe the path of a ray that approaches a mirror parallel to the principal axis.

While goofing off at the ice skating rink, a student takes off her shoes and places each of them on the ice. her friend, a hockey player, then shoots a hockey puck at each shoe. the first puck immediately comes to rest after it collides with the left shoe. the second puck rebounds after it collides with the right shoe. if each hockey puck has the same incoming speed, which shoe has greater speed after the collision? the right shoe. both shoes have the same speed. the left shoe.

In a simplified model of the human eye, the aqueous and vitreous humors and the lens all have a refractive index of 1.40, and all the refraction occurs at the cornea, whose vertex is 2.60 cm from the retina. what should be the radius of curvature of the cornea such that the image of an object 40.0 cm from the cornea’s vertex is focused on the retina?