Umm i am confuse i have a question how to do this work

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).

What is the 17th term in the arithmetic sequence in which a6 is 101 and a9 is 83

Find the average rate of change for the given function drom x=1 to x=2