Answer:
stratified sample
Step-by-step explanation:
A rational number is a number that can be written in the form:

Where p and q are coprimes. We are asked for finite sets, we can rule out options 3 and 4. In the set in option 2 the first element is:

This number cannot be written a ratio. We can rule out option 2.
All the elements in the set from option 1 can be written in the form p/q.Thus, the answer is the first option.
<h3>
Answer: 5 - 4i (choice A)</h3>
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Work Shown:
x = the other number
(5+4i)*x = 41
x = 41/(5+4i)
x = 41*(5-4i)/( (5+4i)*(5-4i) ) ..... see note below
x = 41*(5-4i)/( 41 )
x = (41/41)*(5-4i)
x = 5 - 4i
As a way to check, (5+4i)*(5-4i) = 5^2+4^2 = 25+16 = 41
The rule used is (a-bi)(a+bi) = a^2 + b^2
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Note: I multiplied top and bottom by (5-4i) to get rid of the imaginary term in the denominator.
Answer:
$1.51
Step-by-step explanation:
1.25 lb. of dried fruit : 
0.5 lb. of cereal : 
Cost = $2.30 + $1.19 = 3.49
Money = $5
$5 - $3.49 = $1.51 in change
I supposed you are going to learn about area or volume, just remember length x width x height is volume and length x height is area