<em>Structure and Function of ArthropodsArthropods range in length from about 1 millimeter to 4 meters (about 13 feet). They have a segmented body with a hard exoskeleton. They also have jointed appendages. The body segments are the head, thorax, and abdomen. </em><span><em> In some arthropods, the head and thorax are joined together as a cephalothorax.</em></span>
that's all wrong the real answer is b.99.3
Two examples of radioisotopes that can be used are carbon-14 to determine the age of fossils. Second, we can use iodine-131 to treat thyroid disease.