Represent the following expressions as a power of the number a (a≠0):

(a^2a^4)÷a^−3/a÷(a^2a^3)^4

(a^2a^4)÷a^−3 = (a^2a^4)*a^3 = a^6*a^3 = a^9

a/(a^2a^3)^4 = a/(a^5)^4 = a/a^20 = a^-19

a^9÷a^-19 = a^9 * a^19 = a^28

To express the given expressions as a power of the number "a", we can make use of the laws of exponents. Let's break down the expressions step by step:

Expression 1: (a^2a^4)÷a^−3

To simplify this expression, we can apply the multiplication and division properties of exponents. When dividing with the same base, we subtract the exponents.

(a^2a^4)÷a^−3 = a^(2+4-(-3))

Simplifying the exponent with the negative sign:

= a^(2+4+3)
= a^9

So, the first expression (a^2a^4)÷a^−3 can be represented as a^9.

Expression 2: a÷(a^2a^3)^4

Here, we need to simplify the expression within the parentheses (a^2a^3) first.

(a^2a^3) = a^(2+3)
= a^5

Now, let's combine this result with the outer expression.

a÷(a^2a^3)^4 = a÷(a^5)^4
= a÷a^(5*4)
= a÷a^20
= a^(1-20)
= a^(-19)

Therefore, the second expression a÷(a^2a^3)^4 can be represented as a^(-19).

To summarize:

Expression 1: (a^2a^4)÷a^−3 can be represented as a^9.

Expression 2: a÷(a^2a^3)^4 can be represented as a^(-19).