Properties of Definite Integrals

I. The definite integral $\int_0^2 (3*x^2)\,dx$ yields the exact area under $f(x)=3*x^2$ from $x=0$ to $x=2$.

II. The area under the curve must always be equal to the value of the definite integral.

III. Reversing the limits of integration changes the sign of the definite integral.

Which of these statements are true regarding definite integrals and area?