Which set of ordered pairs is a function? {(-2,1),(-4, 2), (0, 3), (4,1),(-2,5)}
{(-1,5), (-1,4) (-1,3), (-1, 2), (-1,1)}
{(-6,-4), (-4,-2), (0,0).(-4, 2).(-6,4)}
{(-5,1). (-3, 2), (-1,3), (1,4), (3,5)}

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).

Jayne is studying urban planning and finds that her town is decreasing in population by 3% each year. the population of her town is changing by a constant rate. true or false?

15 liters is approximately how many gallons