True or false are all structures made by humans and why

What is the equation of the graph that represents f(x)=x^4 stretched vertically by 2 and shifted up 3 spaces

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).

How far is x from 5 on a number line?