What is f(3)? in the 1st term of arithmetic sequence is 5 and the common difference is 1.5

The decibel level of sound is 50 db greater on a busy street than in a quiet room where the intensity of sound is watt/m2. the level of sound in the quiet room is db, and the intensity of sound in the busy street is watt/m2. use the formula , where is the sound level in decibels, i is the intensity of sound, and is the smallest sound intensity that can be heard by the human ear (roughly equal to watts/m2).

Two streets intersect at a 30- degree angle. at the intersection, the are four crosswalks formed that are the same length. what type of quadrilateral is formed by the crosswalks?

Find the measure of the interior angles of the following regular polygons: a triangle, a quadrilateral, a pentagon, an octagon, a decagon, a 30-gon, a 50-gon, and a 100-gon.