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The Tax Gatherer

[The Bastiat Collection (2011); originally from the second series of Economic Sophisms (1848)]

The Tax Collector (1542) by Marinus van Reymerswale

JACQUES BONHOMME, a vintner.

Mr. LASOUCHE, tax gatherer.

L.: You have secured 20 tuns of w
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20.102 Macroepidemiology (BE.102) (MIT)
This course presents a challenging multi-dimensional perspective on the causes of human disease and mortality. The course focuses on analyses of major causes of mortality in the US since 1900: cancer, cardiovascular and cerebrovascular diseases, diabetes, and infectious diseases. Students create analytical models to derive estimates for historically variant population risk factors and physiological rate parameters, and conduct analyses of familial data to separately estimate inherited and enviro
Author(s): Thilly, William

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Imagine Cup TV Episode 002: WOWZAPP, The Tech Awards, and the Big Board! | Imagine Cup TV

John and Golnaz are back for more and they've been on the road to Helsinki and to Silicon Valley. Check out the latest and greatest from Imagine Cup and watch out for popping toast!

 

edit on WOWZAPP information: there were actually 3000 apps created and the event took place in 120 locations around the world!

Author(s): Golnaz, John Scott Tynes

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Population Standard Deviation - Khan Academy
Defining the population standard deviation as the square root of the population variance. (08:05)
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Arthur's Baby Read-Aloud (Narrated by Kelly Rippa)
This read-aloud is Arthur's Baby written and illustrated by Marc Brown. The narrator is Kelly Rippa. The words appear at the bottom of the screen as they are read by the narrator. D.W. and Arthur find out the challenges and joys of having a new sister in the house. This is a good resource to help build a literacy rich environment in the elementary classroom. It would help struggling readers and/or special education students. 
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The Marxian Doctrine of "Ideology"

[This article is excerpted from volume 2, chapter 12 of An Austrian Perspective on the History of Economic Thought (1995). An MP3 audio file of this chapter, narrated by Jeff Riggenbach, is available for download.]

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2.7 Inferring relationships of common ancestry

Activity 6

0 hours 10 minutes

This clip addresses the question of how one might go about building a tree, or inferring relationships of common ancestry, by recognising evolutionary novelties, or share
Author(s): The Open University

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2.5 What does relationship mean in systematics? W. Hennig

Activity 4

0 hours 5 minutes

In this clip, Dr. Patterson introduces his third systematist, a German entomologist named Willi Hennig. This offers a third meaning of ‘relationship’, which is illustr
Author(s): The Open University

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1.1 Introduction

To the lay person, it might seem surprising that there is any problem with the recognition of higher taxa. The very existence of long-established vernacular names for inclusive groupings of species (e.g. finches, thrushes, parrots and hawks as distinct groups of birds) suggests that higher taxa are self-evident. Accordingly, the task of the taxonomist might seem merely to consist of recognising these groupings and assembling them in a hierarchy of increasingly inclusive categories.

Inde
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4.2 Intermediate forms

In essence, the argument about intermediate forms runs as follows. If whales evolved from a terrestrial ancestor through the accumulation of small differences over time, we should expect to find the fossils of a number of ‘missing links’, i.e. creatures with a mixture of terrestrial and aquatic characteristics. In fact, we might expect to find a succession of such animals, each a little bit more whale-like and a little bit less well adapted to life on land than its predecessor.

To m
Author(s): The Open University

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2.2 Breathing air

A swimming elephant can breathe by holding the end of its trunk out of the water, but if it tried to find its food under the surface, like the desman, it would have to hold its breath. Neither the mammalian lung nor the skin can extract enough oxygen from water to sustain life, so aquatic mammals must come to the surface at intervals to breathe; and all of them – pinnipeds, sirenians and cetaceans – drown if they are prevented from doing so for prolonged periods.

Lungs form 7% of th
Author(s): The Open University

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6.3 Valence-shell electron-pair repulsion theory

The theory of molecular shape that we have been working towards is called valence-shell electron-pair repulsion theory (VSEPR theory). When applied to molecules and ions of the typical elements, its success rate is high. Here is a stepwise procedure that you can follow when applying this theory. It is illustrated with the molecule XeF4 and the ion C1O3. Xenon tetrafluoride is one of the select band of noble gas compounds that were unknown before 1962
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6.1 Introduction

Structural formulae of, for example, hexan-1-ol (Structure 6.1) and PF5 (Structure 5.13) merely tell us the immediate neighbours of any particular atom. They are two-dimensional drawings, which ignore the three-dimensional shapes of the molecules. But in studying the structures obtained by X-ray crystallography in Sectio
Author(s): The Open University

3.4 Outer electronic configurations and the Periodic Table

The essential message of Figure 22 is that the Groups of elements that appear in columns of the Periodic Table usually have atoms with similar outer electronic configurations. Figure 23 incorporates these configurations into our mini-Periodic Table of typical elements; they appear at the top of each Group. They imply that the typi
Author(s): The Open University

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3.3 Electronic configurations and the Periodic Table

Figure 21 has been designed for use in a particular thought experiment. The purpose of the thought experiment is to see how the electronic configuration of the atoms changes as one moves through the Periodic Table from beginning to end. We start with the hydrogen atom, which has one proton and one electron. Then we
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3.2 The electronic configurations of atoms

The quantum theory of the atom tells us that we cannot say exactly where an electron in an atom will be at any particular moment; we can speak only of the probability of finding an electron at a particular point. So the precise orbits shown in the Rutherford model of Figure 1 misrepresent the arrangement of electrons about
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4.4 Further exercises

Exercise 29

In this exercise, take

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4.4 Self-assessment questions and problems

SAQ 25

Find the distance between the numbers 2 − i and 1 + 3i.

Answer

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1.2.1 Try some yourself

1 Without using your calculator, find the following:

  • (a) 102

  • (b) 1002

  • (c) 0.12

  • (d) 0.012

  • (e)
    Author(s): The Open University

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Introduction

This unit shows how partial differential equations can be used to model phenomena such as waves and heat transfer. The prerequisite requirements to gain full advantage from this unit are an understanding of ordinary differential equations and basic familiarity with partial differential equations.

This unit is an adapted extract from the course Mathematical methods and models (MST209
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