Answer:
The greatest common factor is 4 :)
Answer:
- Population: Soil around a former waste dump
- Parameter: Concentrations of toxic chemicals
- Sample frame: Accessible soil around dump
- Sample: 16 soil samples
- Method: Unclear
- Bias: Uncertain if soil samples were randomly chosen
Step-by-step explanation:
The above answer explanation can be more clear by understanding that the population is the soil around the former waste dump and the samples are 16 which were taken from EPA.In report, the method is unclear too.
Answer:
a. closed under addition and multiplication
b. not closed under addition but closed under multiplication.
c. not closed under addition and multiplication
d. closed under addition and multiplication
e. not closed under addition but closed under multiplication
Step-by-step explanation:
a.
Let A be a set of all integers divisible by 5.
Let
∈A such that 
Find 

So,
is divisible by 5.

So,
is divisible by 5.
Therefore, A is closed under addition and multiplication.
b.
Let A = { 2n +1 | n ∈ Z}
Let
∈A such that
where m, n ∈ Z.
Find 

So,
∉ A

So,
∈ A
Therefore, A is not closed under addition but A is closed under multiplication.
c.

Let
but
∉A
Also,
∉A
Therefore, A is not closed under addition and multiplication.
d.
Let A = { 17n: n∈Z}
Let
∈ A such that 
Find x + y and xy


So,
∈ A
Therefore, A is closed under addition and multiplication.
e.
Let A be the set of nonzero real numbers.
Let
∈ A such that 
Find x + y

So,
∈ A
Also, if x and y are two nonzero real numbers then xy is also a non-zero real number.
Therefore, A is not closed under addition but A is closed under multiplication.
Answer:
Step-by-step explanation:
Let's see how well I can explain this.
is the same as a 30 degree angle which is in quadrant 1. If you picture the unit circle, right in the center of it is the origin. If you draw a straight line from 30 degrees and through the center (the origin), you will automatically "connect" with the reference angle of 30 (this is true for ALL angles on the unit circle). This puts us in quadrant 3. In quadrant 3, x is negative and so is y. So the terminal point of the reference angle for 30 degrees has the same exact values, but both of them are negative (again, because both x and y are negative in quadrant 3). I can't see your choices but the one you want looks like this:

Answer:
Step-by-step explanation:
Surface area is the sum of the areas of all faces (or surfaces) on a 3D shape. A cuboid has 6 rectangular faces. To find the surface area of a cuboid, add the areas of all 6 faces. We can also label the length (l), width (w), and height (h) of the prism and use the formula, SA=2lw+2lh+2hw, to find the surface area.