Various Callout shapes available in PowerPoint can be impactors that convey a message, but only when used wisely. You need to attribute and position the callout properly so that your audience does not get lost. Just like any other PowerPoint shape, Callouts take default formatting attributes from the Theme applied to the presentation. You can change their fill and/or outline and also apply a shape effect to them in the same way as you would do for any PowerPoint shape.
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