D. 16.8 units
A radius is half of the diameter, so to get the answer all you need to do is multiply the length of the given radius by 2.
8.4x2= 16.8
There aren't any solutions. I recommend using MathPapa algebraic calculator for problems like this. Here's the link: https://www.mathpapa.com/algebra-calculator.html
The derivative of x^3 is 3x^2.... is that what you were looking for?
Answer:
-14.5
Step-by-step explanation:
-14.5