B: 80
All the sides add up to 20 so adding all four sides make 80
ANSWER
A) 9.4 * 10^-8, 9.25 * 10^-6, 2.5 * 10^3, 7* 10^3
EXPLANATION
The numbers are given in standard form.
The first criteria we will use to order them is the exponents.
The bigger the exponents the bigger the number.
The second criteria is that, if the exponents of any two numbers are the same, then we use the numbers multiplying the powers of 10 to order.

The correct choice is A.
Answer: total cost is $13
Step-by-step explanation:
Answer:
x = 
Step-by-step explanation:
Given
x +
+ (x - 1) = 
Multiply through by 10 ( the LCM of 2 and 5 ) to clear the fractions
10x + 15 + 10(x - 1) = 8
10x + 15 + 10x - 10 = 8
20x + 5 = 8 ( subtract 5 from both sides )
20x = 3 ( divide both sides by 20 )
x = 