Answer:
Stratified sampling
Step-by-step explanation:
The is a type of sampling in which the population of interest is divided into subpopulations and then each subpopulation is randomly sampled.
In this case study, instead of just doing a random sampling of all students, the research divided the population of all students into subpopulations which includes freshmen, sophomores, juniors and seniors and then she makes a random sampling of each of these subpopulations.
Answer:
Step-by-step explanation:
Given the equation 
Step 1;
Expand the bracket at the right hand side of the equation to have:
Taking the reciprocal of both sides:
Answer:
Alicia needs 32ft² of carpet to cover the space
Euclid's form of Geometry! Simple.
Answer:
2/10
Step-by-step explanation:
First you - 20 from 40 (aka 2/10 - 4/10) and you will get 20 (aka 2/10).
