To determine monthly rental prices of apartment units in the San Francisco Bay area, you classify the apartments according to zip code and take a random sample from each of the zip code regions. What sampling method have you employed?-

Explanation:

This type of sampling is where you break the data into groups where there isn't any overlap. Then you select samples from each group. You may select the same amount from each group, or perhaps you select the items based on a weighted proportion. Note how one entire group is not sampled.

Contrast this with cluster sampling where again the data is broken into non-overlapping groups; however, this time we only select a few groups to sample every member of those groups selected. This time entire full groups are sampled.

Here's an example of each

idk

step-by-step explanation:

use that smart brain

x= -3 and

step-by-step explanation:

to find the roots of a cubic, use division or factoring to find the factors then set equal to 0. as this is a difference of cubes, it factors into

where a is the cube root of .

here   this is 27 and the cube root of 27 is 3. so we write using the form:

.

set each factor to 0 and solve for x.

x-3=0

x=3

the quadratic expression does not factor and must be solved using the quadratic formula.

where a = 1, b=3, and c=9

this cubic has two complex roots.