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:
x=23.5
Step-by-step explanation:
90=25-x/2+18
combine like terms
90=43-x/2
subtract 43 from both sides
47= -×/2
47/2= 23.5
x=23.5
or
90-25= 65
65-18=47
47/2=23.5
Factor out the cos<span>θ:
</span>cosθ (2sin<span>θ + sqrt3) = 0
</span>Therefore, the only ways this can happen are if either cosθ = 0 or if (2sin<span>θ + sqrt3) = 0
</span>The first case, cosθ = 0 only at θ <span>= pi/2, 3pi/2.
</span>The second case, <span>(2sin<span>θ + sqrt3) = 0 simplifies to:
</span></span>sin<span>θ = (-sqrt3)/2
</span><span><span>θ = 4pi/3, 5pi/3
</span></span><span><span>Therefore the answer is A.
</span></span>
If he runs 5 kilometers in 30 minutes, at that rate he would run 10 kilometers in an hour.
so 10 kilometers per hour is his speed
Angles RZT, RZS, and TZS form triangle RZT, so they sum to 180. Thus, we have:
110+3s+8s=180
Simplifying, we have:
11s=70
Dividing by 11, we see that:
s=70/11
Therefore, RZS=3s=210/11, and TZS=8s=560/11.
