I believe it's webbed feet
Answer is: <span>an atomic radius.
</span>The atomic radius<span> of a </span>chemical element<span> is a measure of the size of its atom.
</span>The atomic radius varies with increasing atomic number, but usually increases because of increasing of number of electrons.
The atomic radius decreases across the periods because an increasing number of protons, because <span>greater attraction between the protons and electrons.</span>
Mixtures can be classified as <u>homogeneous </u>or <u>heterogeneous</u>.
The base units of length and volume are linked in the metric system. By definition, a liter<span> is equal to the volume of a cube exactly 10 </span>cm<span> tall, 10 </span>cm<span> long, and 10 </span>cm<span> wide. Because the volume of this cube is 1000 cubic </span>centimeters<span> and a </span>liter<span> contains 1000 milliliters, 1 milliliter is equivalent to 1 cubic centimeter.</span>