Answer:
A) stratified
Explanation:
Total call including 6500 'yes' and 4100 'no' are 10600 and on each call there was a fifty cent charge. Total charge becomes 5300 $ so this is very straight forward data. And from this test two types of classes are made with cleared population in each class and such cleared population division is example of stratified sampling so this is right answer.
Answer:
The cost of production and using more efficient resources
Let a, b, and c be the coefficients in the balanced reaction:
a Fe + b Cl₂ → c FeCl₃
Count the atoms that show up among the reactants and products. They should be equal on both sides:
Fe : a = c
Cl : 2b = 3c
Let c = 2. Then a = 2 and 2b = 6, so b = 3.
Then the balanced reaction is
2 Fe + 3 Cl₂ → 2 FeCl₃
Recent data show that phenotypic variation categories such as skin color or facial form most often used to define race.
<h3>What is phenotypic variation?</h3>
Phenotypic variation can be defined as the difference in the observable characters or attributes (phenotypes) of each organism in a specific population such as:
Based on recent data from scientific research, phenotypic variation categories such as skin color or facial form most often used to define race.
Read more on phenotypic variation here: brainly.com/question/22840871
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