According to the empirical rule, if is a random variable that has a standard normal distribution, then approximately 68% of all values fall between –1 and 1. use a table of ‑critical values or software to find this percentage precise to at least two decimal places.

Four Common Tangents, (n = 4)

Step-by-step explanation:

The next to last case is where the centers of the circles are far enough apart that the circles are completely separated. This is probably the most common case, and is defined by the relationship: d > a + b. There are 2 internal common tangents and two external common tangents.

not sure it's help!

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