Answer:

Explanation:
This is an exponential growing: there is a constant growing<em> factor </em>which multiplies the value number of letters sent every week.
The growing factor <em>4 letters every 9.1 weeks</em> means that every 9.1 weeks the number of letters is multiplied by 4.
Then, if the number of weeks is t, the number of times the number of letters increase is t/9.1.
Then, the exponential<em> function</em> <em>that models the number of people who receive the email t weeks since Tobias initially sent the chain letter</em>, has the form:

<em>Tobias initially sent the chain letter to 37 friends</em>; thus, the initial value is 37, and the complete function is:
, where t is the number of weeks since Tobias initially sent the chain letter.
Answer:
I think you mean commutative property. 30 * 8
Step-by-step explanation:
This does not have parentheses around anything. To solve with commutative property switch the digits.
Angle A = 67^0
<span>Angle B = 53^0
</span>
I don't know where D and C are
Answer:
c. Cluster sampling
Step-by-step explanation:
Taking into account that the exercise researcher is looking with limited resources to study a population that is divided, her best option is cluster sampling, which is a method applicable to this type of population, we could select in each group randomly her sample, the observational study is discarded because she does not have much availability of time or resources, nor would the stratified study be useful because she should select subgroups and create them to take samples and this would take more time and resources and sampling systematic is not adequate because it must have all the individuals and after having the list select the sample, but as we know, it is a process that will study the number of individuals so this option is not feasible.
The answer is D becoz of the explanations