Discuss which random sampling techniques are adopted in the following studies. a. A researcher wants to find out the prevalence of anemia in school students. He splits schools into rural, urban, and peri-urban as the prevalence may be quite distinct between these regions. The second step 1 is to take a simple random sample within each categorized area in proportion to the numbers enrolled in the schools in each area.
b. There are 24 canopy trees in the sampling universe of interest, and you want to take 10 measurements from a subset of this group. You number each tree (1-24), put numbers in a hat, and pick ten at random. The tree corresponding to the number is now part of your sampling subset.
c. From the Yellowpage book of the current year, you pick out 20 pet stores at random.
d. A researcher wants to examine the growth patterns of a specific plant growing national wide in U. S.A. Out of 50 states, he selected 10 states at random. Within the selected states, he picks out 15 cities at random in each state. Then He collects the plants from the chosen cities.

step-by-step explanation:

we are given a graph for system of inequalities.

in order to write the system of inequalities for the given graph, we need to find the inequality for each of the line separately.

let us find the slope of dotted line first.

taking two coordinates on the graph.

let us say (0,0) and (3,1).

let us find the slope of the line now.

slope of the dotted line would be =.

y-intercept of dotted line is y=0 only.

plugging slope m= and b=0 in slope-intercept form y=mx+b, we get

.

the line is shaded up of that dotted line.

therefore, for shading up we would take greater than inequality symbol > .

and because it's a dotted line we would take only > symbol in place of = sign in above equation of line.

therefore, inequality for dotted line would be

let us take two points (3,1) and (0,4) on the solid line.

slope of the solid line would be =.

for the solid line we have y-intercept b= 4.

plugging slope m= -1 and b=4 in slope-intercept form y=mx+b, we get

y = -1x + 4.

the line is shaded down of that solid line.

therefore, for shading down we would take less than inequality symbol < .

and because it's a solid line we would take ≤ symbol in place of = sign in above equation of line.

therefore, inequality for solid line would be

hope it you

step-by-step explanation:

sin(7pi/6 - pi/3)  

= sin(7pi/6 - 2pi/6)  

= sin(5pi/6)  

= sin(pi - pi/6)  

= sin(pi/6)  

= 1/2  

sin 7pi/6 - sin pi/3  

= sin (pi + pi/6) - sin pi/3  

= -sin pi/6 - sin pi/3  

= -1/2 - sqrt(3)/2  

= -(1+sqrt(3))2

nlgqer

step-by-step

x² + 3x + 7 = 0       [ax² + bx + c]

a = 1

b = 3

c = 7

quadratic formula:

    (+/- is this ±)

plug in the numbers into the variables

your answer is a