Compare penetrability of compressed vs. intermediate soil

Farmers know that driving heavy equipment on wet soil compresses the soil and injures future crops. Here are data on the "penetrability" of the same type of soil at 2 levels of compression. Penetrability is a measure of how much resistance plant roots will meet when they try to grow through the soil.

(a) make stemplots to investigate the shape of the distributions. The penetrabilities for intermediate soil are skewed to the right and have a high outlier. Returning to the source of the data shows that the outlying sample had unusually low soil density, so that it belongs in the "loose soil" class. We are justified in removing the outlier.

(b) We suspect that the penetrability of compressed soil is less than that of intermediate soil. Do the data (with outlier removed) support this suspicion?

Solution Summary

This solution provides a statistical significance test to compare the penetrability of compressed soil to that of intermediate soil. Stemplots to investigate the shape of compressed and intermediate soil distributions are included.

1.1 Is the soil found at your home the same as the soil in front of the chemistry building on your campus or local shopping mall? How does it differ?
2.1 What properties of soil and its components could be measured to determine whether two soil samples are consistent with having a common origin?
3.1 How can we identify what

A child's toy consists of a piece of plastic attached to a spring. The spring is compressed against the floor a distance of 2.00 cm, and the toy is released. If the toy has a mass of 90 g and rises to a maximum height of 50.0 cm, estimate the force constant of the spring (in N/m).
I need help on which equation/formula to use a

21) Use synthetic division to find: f(?2)
f(x)=2x3?3x2+7x?12 21)
22) For the function f(x) = ?x3 + 8x2 ? 40
Show how to use synthetic division to find out if -1 is a zero.
22)
23) One of the zeros of the function f(x) = ? 7x2 + 17x ?15 is 2-i. Find all the other zeros.
23) ____________________
24) Use the intermediate val

Please provide solution for (a) and (b) with explanation of how it was derived.
Early groups used Pb plumbing in their homes more than 2000 years ago. This Pb pipe has since corroded in the soil to form cerrusite (PbCO3) and hydrocerrusite ( Pb3(CO3)2(OH)2 ).
Essington et al., 2004. The soil mineralogy of lead at Ho

The following percentages of three pesticides added to a soil remained after increasing times.
Time (days) Diazinon % Benefin % Terbutol %
0 100 100 100
15 18.7 no data no data
30 1.50 57.5 94.3
60 0.30 29.0 80.2
90 0.01 14.5 73.7
180 0.01 7.50 51.3
1) Fit the decomposition data f

1. You are loading a spring loaded dart gun and do an amount of work W such that the spring is only 1/3 compressed. How much additional work must you do to fully compress it from 1/3 to fully compressed? Answer in terms of W.
2. A large man tosses a small child onto a large pile of leaves. During the toss, the man exerts ___

I need help with the following questions. Please show your work so I can practice with other problems.
Thank you
An oil company purchased an option on land in Oklahoma. Preliminary studies assigned the follwing prior probabilities.
P(high-quality oil) = .50
P(medium-quality oil) = .20
P(no oil) = .30
a. What is t

A 2.0 kg block slides along a horizontal surface with a coefficient of friction µk = 0.30. The block has a speed of v = 1.2 m/s when it strikes a massless spring head-on (as in Fig. 8-18).
(a) If the spring has a force constant k = 120 N/m, how far is the spring compressed?
(b) What minimum value of the coefficient of s

Indian mustard (brassica juncea) can be used for phytoremediation of lead in soil because it has the ability to hyper accumulate lead by a factor of 17. The average crop yield is about 4.0 kg per square metre.
a) Calculate the expected plant concentration of lead if the soil contains 280 ppm.
b) What mass of lead would p