Arandom sample of n = 12 four-year-old red pine trees was selected, and the diameter (in inches) of each tree’s main stemwas measured. the resulting observations are as follows: 11.3 10.7 12.4 15.2 10.1 12.1 16.2 10.511.4 11.0 10.7 12.0a. compute a point estimate of o, the population standard deviation of main stem diameter. what statistic did you use toobtain your estimate? b. making no assumptions about the shape of the population distribution of diameters, give a point estimate for thepopulation median diameter. what statistic did you use to obtain the estimate? c. suppose that the population distribution of diameter is symmetric but with heavier tails than the normal distribution. give a point estimate of the population mean diameter based on a statistic that gives some protection against thepresence of outliers in the sample. what statistic did you use? d. suppose that the diameter distribution is normal. then the 90th percentile of the diameter distribution is u+ 1.280 (so90% of all trees have diameters less than this value). compute a point estimate for this percentile. (hint: first compute anestimate of a in this case; then use it along with your estimate of s from part (a].)

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

(w – 2.5)(w + 2.5)

(–4v – 9)(–4v + 9)

step-by-step explanation:

they charge the same amount at 20 minutes.

step-by-step explanation:

since no one answered yet i will give it a shot, not completely sure tho.

i think it should be y=cos(x+2pi), (third answer, answer c)

good luck.