4.A counterexample can be used to show that a conjecture is false. Below are three conjectures students made after visiting a zoo. Write a counterexample that shows that each
conjecture is false
a. There are always more elephants in a zoo than giralles.
b. The oldest leatherback sea turtle in captivity is 33 years old.
c. American bison are never over 6 feet tall.

Step-by-step explanation:

Yes y varies directly with x.

From the equation of a straight line,

y = mx+c, calculating the gradient (m) after doing the plotting with the given coordinates, (m) =4/5.

Therefore the equation of the line is

y= 4/5x + c and c is the point at which the line intersected the y - axis which is roughly 15.

Therefore the equation of the line id

5y = 4x + 75.