Write the expression as an exponent: 0.4^5·0.16

Which statement is always true? a negative exponent cannot be part of an expression's numerator. a negative base raised to the power of 2 has a negative value. a negative base raised to the power of 2 has a positive value. any number to the first power is zero.

Write 17/20 as a decimal and as a percent.

Steve wants to develop a way to find the total cost of any item including sales tax. the sales tax in his city is 6%. his friend jenna writes the expression x + 6x where x is the cost of the item. explain whether her expression is correct based on the situation.