Answer: <em>In order to calculate the mechanical advantage of a wheel and axel, you can divide the radius of the wheel by the radius of the axle. If a wheel's radius is 60cm and its axle is 30cm, what is the mechanical advantage of the wheel and axle? The output force of the wheel and axle is 2 times greater than the input force.</em>
<em />
<h2>
</h2>
B
The Ardi fossil is believed to be 4.4 million years old, providing evidence that humans have been on Earth for 4 million years.