Conservationists have despaired over destruction of tropical rain forest by logging, clearing, and burning." these words begin a report on a statistical study of the effects of logging in borneo. here are data on the number of tree species in 12 unlogged forest plots and 9 similar plots logged 8 years earlier: unlogged 22 18 22 20 15 21 13 13 19 13 19 15 logged 17 4 18 14 18 15 15 10 12 use the data to give a 90% confidence interval for the difference in mean number of species between unlogged and logged plots. compute degrees of freedom using the conservative method. interval: to

[0.841;6.879]

Step-by-step explanation:

Hello!

You have two independent samples:

Sample 1

X₁: tree species in an unlogged plot.

n₁= 12 plots

Unlogged 22 18 22 20 15 21 13 13 19 13 19 15

Sample 2

X₂: tree species in a plot logged 8 years earlier

n₂= 9

Logged 17 4 18 14 18 15 15 10 12

The objective of this experiment is to estimate the difference between the means of the number of species on the unlogged plots and the logged plots. Symbolically: μ₁-μ₂

To be able to estimate the difference between the two population means, I'll assume that both variables have a normal distribution and use a pooled t-statistic for the Confidence interval. (I did a quick F-test for variance homogeneity, population variances are unknown but equal)

The formula is:

(X₁[bar]-X₂[bar])±*(Sₐ√(1/n₁+1/n₂))

Where

sample mean sample 1 X₁[bar]= 17.50

sample mean sample 2 X₂[bar]= 13.64

S₁= 3.53

S₂= 4.50

Sₐ²= (n₁ - 1)S₁² + (n₂ - 1)S₂² = 11*(3.53)² + 8*(4.50)² = 15.74

                   n₁+n₂-2                            19

Sₐ= 3.96

Now replace the values in the formula:

(X₁[bar]-X₂[bar])±*(Sₐ√1/n₁+1/n₂)

[(17.50-13.64) ± 1.729*(3.96*√(1/12+1/9))]

[3.86 ± 3.019]

[0.841;6.879]

With a confidence level of 90%, you'd expect that the interval [0.841;6.879] contains the difference between the means of the number of species on the unlogged plots and the logged plots.

I hope it helps!

∠lno ≅ ∠lnm

∠oln ≅ ∠mln

step-by-step explanation:

given   that triangle lno is congruent to triangle lnm.

we have to fill up the blanks in the given question.

according to above order of congruency   kept in mind we can say that

∠lno ≅ ∠lnm

∠oln ≅ ∠mln

ln ≅ ln due to common in both.

hence, by sas congruency,

the side angle side rule   states that if two sides and the included angle of one triangle are congruent to another triangle, then these two triangles are congruent.

solution:

the given function is ,

      =

the three roots of this quadratic function is , 0 ,8 and 10.all the roots are real and rational.

if a quadratic equation is of the form ,

sum of the roots = a + b +c= 0+8+10=18=  

product of roots taken two at a time = a b + b c+ c a = 0+80+0=80 =  

product of roots = a b c = 0=  

there are 11 doors in a hall starting from 0 to 11.the entry in the hall is permitted through gate number 0 and exit is allowed through only gate number 8 and 10.so, three roots(0,8,10) of quadratic function is given by entry and exit route of this hall.