The two dot plots below show the heights of some sixth graders and some seventh graders: Two dot plots are shown one below the other. The title for the top dot plot is Sixth Graders and the title for the bottom plot is Seventh Graders. Below the line for each dot plot is written Height followed by inches in parentheses. There are markings from 52 to 57 on the top line and the bottom line at intervals of one. For the top line there are 2 dots above the first mark, 1 dot above the second mark, 1 dot above the third mark and 2 dots above the fourth mark. For the bottom line, there is 1 dot for the first mark, there is 1 dot above the second mark, there is 1 dot above the third mark, there is 1 dot above the fourth mark and there are two dots above the sixth mark.

The mean absolute deviation (MAD) for the first set of data is 1.2 and the MAD for the second set of data is 1.7. Approximately how many times the variability in the heights of the sixth graders is the variability in the heights of the seventh graders? (Round all values to the tenths place.)

1.2
1.4
2.4
2.8

The Pony Express
Chapter 1
At A Nation's Crisis
The Pony Express was the first rapid transit and the first fost mail line across the continent from the Missouri River to the Pacific Coast. It was a system
by means of which messages were carried swiftly on horseback across the plains and deserts, and over the mountains of the far West It brought the
Adontic coost and the Pacific slope ten days nearer to each other.
It had a brief existence of only sixteen months and was supplanted by the transcontinental telegraph. Yet it was of the greatest importance in
binding the East and West together at a time when overland travel was slow and cumbersome, and when a great national crisis made the rapid
communication of news between these sections an imperative necessity.
The Pony Express marked the highest development in overland travel prior to the coming of the Pacific railroad, which it preceded nine years.
It, in fact, proved the feasibility of a transcontinental road and demonstrated that such a line could be built and operated continuously the year
around-a feat that had always been regarded as impossible.
The operation of the Pony Express was a supreme achievement of physical endurance on the part of man and his ever faithful companion, the
horse. The history of this organization should be a lasting monument to the physical sacrifice of man and beast in an effort to accomplish
something worthwhile. Its history should be an enduring tribute to American courage and American organizing genius.
Read this line from the Pony Express excerpt
It hod a brief existence of only sixteen months and was supplanted by the transcontinental telegraph.
Based on the corres, what does the word "supplanted" mean? (5 points)
Defeated
Joined
Replaced
Os
Oo
Unearthed