What is the sum of the geometric series?
if you could explain how to solve it, that would me a lot

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).

If a || b and b | y, then ? a) x || y. b) x | a. c) a | y. d) a || y.

Which expression is equivalent to -5(3x - 6/7)