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Quill teaches a topic, then quizzes you

Pick a topic (how vaccines work, how a ball flies or how money grows) and how much you know; the basics skip the first page. A short lesson, one idea and one picture a page, then one question: a miss gets a page on why. Say when to quiz you again, and a calculator comes up to play with, with three cards in your review. It runs in the site chat too: say teach me something and quiz me.

Quill

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Quill

A topic to a quiz

Step 1 of 9

Five minutes, then a quiz

Pick a topic. I teach it one idea a page, with a picture each, then ask you one question. What you learn becomes cards you review later.

Pick a topic
A short lesson
One question
A calculator to play with

What do you want to learn?

Know the basics? I skip the first page.

How much do you know already?

Your cells read the recipe

Ribosomes out in the cytoplasm read the mRNA and build the spike protein, the same shape that sits on the virus. It never goes near your DNA.

Instructions in a bubble

An mRNA vaccine is a recipe for one protein, wrapped in a tiny bubble of fat. The shot goes into your arm and the bubble slips into nearby cells.

Gravity only pulls down

Leave the air out and nothing slows the forward part. Gravity takes 9.8 m/s off the climb every second, then pulls it back down.

A throw is two motions

Forward at a steady speed, and up then down. Put the two together and you get the arc.

Forward: steady
Up and down: gravity
Together: an arc

Interest earns interest

Leave the $5 in. Next year you earn 5% of $105, not $100. Each year the new coins are a little bigger. That is compounding.

Interest is rent on money

Put $100 in at 5% a year and the bank pays you $5 for using it. That $5 is the interest.

Your body learns, the recipe fades

Your immune system sees the spike and makes antibodies that fit it. The mRNA breaks down in days. The memory cells stay.

Antibodies fit the spike
mRNA gone in days
Memory cells stay

Where is the mRNA read?

In the cytoplasm

Ribosomes in the cytoplasm, the jelly around the nucleus, read it like a recipe. It never reaches the nucleus, where your DNA is kept.

Three cards from this lesson go in your review for then.

When should I quiz you again?

Speed and angle set the distance

Throw twice as fast and it goes four times as far. Too steep and it spends its speed climbing; too flat and it lands early.

Which angle throws farthest?

45 degrees goes farthest

Halfway between flat and straight up splits the speed evenly between climbing and going forward. 30 and 60 land on the same spot, short of it.

Time does the heavy lifting

At 7% a year money doubles about every 10 years. The rule of 72: divide 72 by the rate to get the years to double.

7%: double in 10 years
Twice more: x4 in 20
40 years: x16

$100 at 10% a year, compounded. After 2 years?

$121

Year one pays 10% of $100, $10. Year two pays 10% of $110, $11. The extra dollar is interest on interest.

Drawing the screen...

flow@study study-quiz

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