About half of the world’s population of 7.8 billion people live in urban areas. How many people live in urban areas?

What is the greater volume 72 quarts or 23 gallons

Which function has an inverse function? a. f(x)= |x+3|/5 b. f(x)= x^5-3 c. f(x)= x^4/7+27 d. f(x)= 1/x²

Two years ago a man was six times as old as his daughter. in 18 years he will be twice as old as his daughter. determine their present ages.