How does Michael Sadler build understanding of the working conditions of child laborers? A by showing how Crabtree's experiences affected him as an adult B by asking Crabtree to describe the factory tasks he performed as a child laborer C by showing how Crabtree's negative experiences are common among child laborers D by asking Crabtree about his hours, punishments and home life as a child laborer

lee and grant, both of whom held the highest rank in their respective armies, had known each other slightly during the mexican-american war (1846-48) and began their dialogue by exchanging awkward personal inquiries. characteristically, grant had arrived in his mud-splattered field uniform while lee had turned out in full dress attire, complete with sash and sword.

explanation:

a hypothesis is an expected answer to a question, usually based on some theory or prior research. hypothesis testing is a method of determining the viability of a hypothesis. let’s use the us presidential election as an example. there are many hypotheses (questions) about how people feel or whom they will vote for. the only way to know the 100% “truth” about the answers to these questions is to ask every single possible voter – something that is impossible, expensive, time consuming etc. instead, we take samples and use statistics to make “best guesses” about the answer to a particular hypothesis. we never know for sure if our conclusion is right at the time we accept/reject it, but these techniques, when used appropriately can get us close to the truth most of the time (which is a lot better than guessing, flipping coins or throwing darts to get answers).

the tricky part about hypothesis testing is that we have to think somewhat backwards about it – we have to test what is known as the “null hypothesis”. as an example, the hypothesis might be “obama is more popular than romney” while the null hypothesis is “there is no difference in popularity between obama and romney”. we focus on the null hypothesis because it tells us exactly what the expected value of our tests should be (obama popularity = romney popularity) and we can collect data and see if it comes out that way (see next section on “significance”). if it does, then we “accept the null hypothesis” and reject our original hypothesis. if the null hypothesis is disproven, we look at the data to see if our original hypothesis holds (obama> romney).