Top. A horizontal asymptote is a y-value which a function approaches. The asymptote is parallel to x axis, so is of the form y = a, for all real values of a. Thus if f(x) = y is a function, then y = a, becomes undefined for the function, then the line y = a, is called the asymptote for the function y = f(x).
The African armyworm (Spodoptera exempta) also called okalombo, kommandowurm, or nutgrass armyworm, is an African moth. It is a very deleterious pest, capable of destroying entire crops in a matter of weeks.
Also called measuring worms, spanworms, loopers and cankerworms, inch worms are larvae, and are usually considered pests because of the damage they inflict on trees, plants and shrubs. Inch worms measure about 1 cm. in length, and can be pale green, reddish-green, dark brown or black. The head is pale to dark green, and is frequently covered with black spots. Pale lines run down the length of the body, and a dark stripe runs down the back.