Answer:
a) cluster sampling
Step-by-step explanation:
In cluster sampling method, each member of a population is assigned to one and only one group.This means clusters are formed through probability method usually a simple random sampling.The participants in the clusters are the only one to be surveyed.
In this example, simple random sampling is used to identify 12 home rooms(cluster) where a group of 20 students (participants) in each room is given the survey.
Answer:
x = (5/3 , 7)
Step-by-step explanation:
Answer:
b = -a
Step-by-step explanation:
Since a and b are equally distant to zero but in opposite directions, a and b are opposites, or additive inverses.
The sum of additive inverses is zero.
a + b = 0
b = -a
Answer:
Step-by-step explanation:
starting point: 140 feet below sea level.=-140
she then decends= 7(4.5)=31.5
-140-31.5=-171.5
finally she ascends 112.2 feet
-171.5+112.2=-59.3 feet or 59.3 feet below sea level