767 rounded to the nearest ten and hundred

Guests at an amusement park must be at least 54 inches tall to be able to ride the roller coaster. which graph represents the set of heights that satisfy this requirement?

Show your workcan a right triangle have this sides? *how to prove it without using the pythagorean theorema*

Let f(x) = 5/x and g(x)=2x2+5x. what two numbers are not in the domain of f o g