... <看更多>

Under the "math operations" button on the equation bar, there's the symbol you are looking for. ... <看更多>

I'm not sure about the best way to display multi-line annotations. If you stick to a single line you can get a pretty readable annotation using: ... <看更多>

... <看更多>

We'll use ˉx (read “x-bar”) to represent the mean of the height variable. ... +xn”, we can use the uppercase sigma symbol ∑ to represent summation of all ... ... <看更多>