He can have 20 different choices.
It is a branch of mathematics that deals with the occurrence of a random event.
Earl can choose gold or silver= 2 choices.
One of 5 different gemstone= 5 choices.
2 choices for round or square.
So total choices he have
=2 * 5 * 2
=20 different choices.
Hence, he have 20 different choices.
Learn more about probability here:
brainly.com/question/11234923
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