Answer:
Systematic sampling
Step-by-step explanation:
An EPA contractor needing to test the concentration of a substance in ten samples out seventy samples provided form a single source at regular time intervals.
For the contractor to effectively carry out the testing he has to employ a Non-probability system of sampling which is called Systematic sampling, because in systematic sampling we can assume the population size (x ) which in this case is 70 and the sample size( n ) to be 10
He will have to select ; ( x / n )^th of the sampling frame for best results
Answer:
0.09 average effect
Step-by-step explanation:
Given that the t statistics = 1.54
Sample size (n) = 25
Therefore, variance = t²/n
Variance = 1.54²/25
Variance = 2.372/25
Variance = 0.09
Answer:
Step-by-step explanation:
88 / sides of a square
88 / 4 = 22
each side is 22m
To solve these kinds of problems, it is necessary to isolate x:
9(2x + 1) <span>< 9x - 18
Distribute 9:
18x + 9 </span><span>< 9x - 18
Subtracting 9 from both sides of the equation:
18x + 9 - 9 </span><span>< 9x - 18 - 9
18x </span><span>< 9x - 27
Subtracting 9x from both sides of the equation:
18x - 9x </span><span>< 9x - 27 - 9x
9x </span><span>< -27
x </span><span>< -3
Therefore, values of x </span><span>< -3 will satisfy the given equation.</span>
Answer:
the answer is the letter a) -sin x
Step-by-step explanation:
Simplify the expression.
sine of x to the second power minus one divided by cosine of negative x
(1−sin2(x))/(sin(x)−csc(x))
sin2x+cos2x=11−sin2x=cos2x
cos2(x)/(sin(x)−csc(x))csc(x)=1/sin(x)cos2(x)/(sin(x)− 1/sin(x))= cos2(x)/((sin2(x)− 1)/sin(x))sin2(x)− 1=-cos2(x)cos2(x)/(( -cos2(x))/sin(x))
=-sin(x)