To select a sample of five children from a class of 30, a researcher puts each child’s name on a slip of paper, then shuffles the papers in a hat and randomly picks five names. What kind of sampling is being used?

We conclude that  a researcher  used simple random sample.

Step-by-step explanation:

We know that select a sample of five children from a class of 30, a researcher puts each child’s name on a slip of paper, then shuffles the papers in a hat and randomly picks five names.  

We conclude that  a researcher  used simple random sample.

Because every children  has an equal chance of being included in the sample.

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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