Answer:
63.6mm² (the last option)
Step-by-step explanation:
the formula for calculating the area of a circle is πr², where r is the length of the radius.
in this case, we know that 9mm is the length of the diameter of the circle, so we can divide that by 2 to get 4.5mm for the length of the radius.
the question has instructed us to use 3.14 for π (pi), so we can substitute these values into the formula:
πr² = 3.14 × 4.5² = 63.585mm²
we can now round this to the nearest tenth to get 63.6mm², which would be the last option.
i hope this helps! :D