<h3>hello!</h3>
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In order to find the diameter, we need to multiply the radius times 2, because the radius is one half (
) of the diameter.
We are given that the radius is:-

Multiply it times 2:-

Hence, the diameter is equal to:-

[Enter 4]
diameter:
in.
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<h3>note:-</h3>
Hope everything is clear; if you need any clarification/explanation, kindly let me know, and I will comment and/or edit my answer :)