The two graduates with the greatest GPA from each of 14 randomly selected law schools were recruited to investigate a new method of preparation for a law exam. For each school, one student was randomly assigned to prepare using the standard method and the other student was assigned to prepare using the new method. At the end of the preparation, all 28 students were given the same exam, and their scores were recorded. Why can we conclude cause and effect from this type of study

Incomplete question. The missing question read;

Which of the following best describes why a matched-pairs design is an appropriate design for the investigation?

a. Each graduate was randomly assigned to one method.

b.  The law schools were randomly selected.

c.  Each method served as a block.

d.  The sample size was less than 30.

e.  Each law school served as a block, and the graduates were paired within each law school and randomly assigned to one of the two methods.

e.  Each law school served as a block, and the graduates were paired within each law school and randomly assigned to one of the two methods.

Step-by-step explanation:

Note, the matched pairs design is typically used when the experiment has two independent variables (treatment conditions), so the subjects of the experiment are grouped into pairs based on some common variable relationship they have before been randomly assigned to the treatment conditions.

In this case, the graduates were paired within each law school and randomly assigned to one of the two methods (the two treatment conditions).

since your problem is x^4 = 81, what you have to undeo is the "to the fourth power" part.

the inverse (opposite operation) of "to the fourth power" is "to the fourth root".

  (x^4) ^ ¼   = 81 ^ ¼  

  81 = 3^4     so (3 ^ 4) ^ ¼   =   3 ^ 1   = 3

by hand: (3 ^ 4) ^ ¼   =   3 ^ (4 x ¼) = 3 ^ 1   = 3   (when you take a power to a power, multiply the exponents.)

or, do it by calculator. one way of finding the fourth root is to use ^ (1/4)

step-by-step explanation: