68. Here's how I did it, since there's 360° in a circle, and CE is through the center
Applying the rule of exponent, the equivalent expression is: 
<h3>What is the Rule of Exponents?</h3>
One of the rules of exponents is given as,
.
Therefore, given:
(x9yz4)5
To find the equivalent expression, apply the rule of exponents as shown below:

Therefore, applying the rule of exponent, the equivalent expression is: 
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