Solution :
Sampling may be defined as the technique of selecting the individual members or the subset of the population to make a statistical inferences and estimates the characteristics of the entire population.
There are several sampling methods. This includes : Systematic sampling, clustered sampling, stratified sampling, quota sampling, judgement sampling, random sampling, convenience sampling and many more.
In the context, the sampling methods for each of the descriptions are :
a). The researcher use computer program to randomly choose a sample of 30 mice of the 1000 mice for using her study
--- Simple Random
b). The researcher chose the 1st 30 mice as she can reach the door to the mouse room
--- Convenience sampling
c). The mice those whose are kept in the cages on 10 various shelves in mouse room. The researcher or the experimenter chose the three mice from each shelve.
---- Stratified sampling
d). Each of the cage have 5 mice and the researcher randomly chooses 6 cages for her study
----- Cluster sampling
e). The researcher generates the list of the identification numbers which has been sorted from the smallest to the largest. The researcher randomly picks 1 mouse form the list and selects every 4 mouse until the researcher has 30 mice.
---- Systematic sampling
I think the answer is 2476/825
Answer:
D
Step-by-step explanation:
Let's substitute a for x²:
x^4 - 3x² - 4
a² - 3a - 4
Now, this looks like something that is much more factorisable:
a² - 3a - 4 = (a - 4)(a + 1)
Plug x² back in for a:
(a - 4)(a + 1)
(x² - 4)(x² + 1)
The first one is a difference of squares, which can be factored into:
x² - 4 = (x + 2)(x - 2)
The second one can also be treated as a difference of squares:
x² + 1 = x² - (-1) = (x + √-1)(x - √-1) = (x + i)(x - i)
The answer is (x + 2)(x - 2)(x + i)(x - i), or D.
Answer:
Required equation : 
Together they can paint the same room in 2.25 hours or 2 hours 15 minutes.
Step-by-step explanation:
It is given that Dale Horton can paint a certain room in 3 hours.
One hour woks of Dale Horton = 1/3
Kathy Garcia can paint the same room in 9 hours.
One hour woks of Kathy Garcia = 1/9
Let together they can paint the same room in t hours.
One hour woks of both = 1/t
After reciprocal we get
1 hour = 60 minutes.
0.25 hour = 15 minutes.
Therefore, together they can paint the same room in 2.25 hours or 2 hours 15 minutes.
Arc length = radius * central angle (in radians)
central angle = arc length / radius
central angle = 7 / 7
central angle = 1 radian
central angle = 57.296 degrees
