Month: March 2017

Lifestyle, history: how was acetaminophen discovered?

The tutor shares a few facts from his recent research of pain medications. In 1886, Doctors Arnold Cahn and Paul Hepp were trying naphthalene as a treatment for intestinal worms. They ordered more, but a pharmacist mistakenly sent acetanilide. One

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English: terror vs horror

Tutoring English, the horror genre can be prominent. The tutor examines the difference between terror and horror. Apparently, terror refers to the dread of anticipating an attack. Just as likely, the nature of the attack is unknown. When someone is

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Chemistry: Graham’s Law of Effusion

Tutoring chemistry, you may mention kinetic energy of particles, diffusion, and effusion. The tutor gives a brief explanation. In my post from Jan 18, 2017, I define effuse: it means to escape from a container through a porous boundary. Graham’s

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Perl: int() function: isolating a digit

Tutoring computer science, extracting a digit is a suggested exercise. The tutor shows a use of Perl’s int() function. Let’s imagine you want to find the hundred-thousands digit of an input number. You can do so with the following code:

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Geography: what is the Dahomey Gap (aka Togo Gap)?

Tutoring geography, you notice features on maps. Apparently, the Dahomey Gap, possibly aka the Togo Gap, is a strip of dry woodland that runs north from the coast of Benin, Togo, and eastern Ghana. The Gap divides the equatorial rainforest

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Statistics, spreadsheets: confidence interval for the mean, population standard deviation unknown: CONFIDENCE.T() function on LibreOffice Calc

Tutoring statistics, the tutor is happy to share the CONFIDENCE.T() function from LibreOffice Calc. My last couple of posts (here and here) I’ve talked about confidence intervals for the mean. Yesterday I mentioned finding one using Excel or LibreOffice Calc’s

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Statistics, spreadsheets: confidence interval for population mean: CONFIDENCE() function on Excel and LibreOffice Calc

Tutoring statistics, you realize how convenient using a spreadsheet can be. In yesterday’s post I mentioned some theoretical points about two-sided confidence intervals for the population mean. On the practical side, if you simply need a confidence interval for the

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Statistics: confidence interval for the mean (two sided)

Tutoring statistics, confidence intervals are important. A two-sided confidence interval for the population mean is given by sample_mean – (standard_dev/n1/2)*sig_factor, sample_mean + (standard_dev/n1/2)*sig_factor The sig_factor (significance factor) depends on the certainty (confidence level) with which we want the confidence interval

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Battery output vs discharge rate: Peukert’s Law

Tutoring physics or chemistry, you might encounter Peukert’s Law, although it’s probably used more by industry. In my March 2 post I mentioned reserve capacity and Amp*hours as two ways to measure a battery’s potential output. Numerically they are convertible

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English: what is a lido?

Tutoring English, finding the precise word is helpful. lido: a beach resort that is accepted as a good place to be seen. (Merriam-Webster) An outdoor recreation area centered around aquatic activities. (Collins) Short words, packed with meaning but seldom used,

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