91Ó°ÊÓ

Simplify each of the following expressions as completely as possible. Final answers should be expressed with positive exponents only. (Assume that all variables represent positive quantities.) $$5^{-2}$$

Simplify each of the following expressions as completely as possible. Final answers should be expressed with positive exponents only. (Assume that all variables represent positive quantities.) $$a^{-4}$$

Simplify each of the following as completely as possible. $$\left(4 x^{4}\right)^{3}$$

Multiply out each of the following. As you work out the problems, identify those exercises that are either a perfect square or the difference of two squares. $$(x-5)(x-4)$$

Multiply and simplify each of the following. Whenever possible, do the multiplication of two binomials mentally. $$t^{2}\left(5 t+t^{4}-t\right)$$

Convert each number into scientific notation. $$70$$

Simplify each of the following expressions as completely as possible. Final answers should be expressed with positive exponents only. (Assume that all variables represent positive quantities.) $$\frac{1}{5^{-2}}$$

Multiply and simplify each of the following. Whenever possible, do the multiplication of two binomials mentally. $$4 x y(3 y z)(-5 x z)$$

In Exercises \(1-18,\) answer the following questions: (a) How many terms are there? (b) What is the degree of each term? (c) What is the degree of the polynomial? $$2^{4} x^{3} y^{5}$$

Simplify each of the following as completely as possible. $$\left(x^{4} x^{3}\right)^{2}$$