The semicircle comes out towards we the viewer, then it goes upwards, and what one gets is 1/2 a sphere. If one keeps on rotating in the direction of the arrow eventually winding up where one started, the result is a full sphere.
4s + 5 = 19 First, subtract 5 from both sides. / Your problem should look like: 4s = 19 - 5. Second, simplify 19 - 5 to 14. / Your problem should look like: 4s = 14. Third, divide both sides by 4. / Your problem should look like: s = . Fourth, simplify to . / Your problem should look like: s = which is the answer.