Plz help with these fast!

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 anwers for 9+2x=5x-3-x

How long does it take natsumi to clean up after she is done? table: .area time30. 245. 2.7560. 3.5