The biceps and triceps act against one another to bend and straighten the elbow joint
What happens in nuclear fusion reaction is that<span> four hydrogen </span>nuclei combine in a <span>proton-proton </span><span>fusion </span><span>to form one </span>helium atom. In the process of fusing to form the helium atom, some of the mass of the hydrogen atoms is converted into vast amounts of energy, which is released.
Answer:
Hard
Explanation:
it is hard because these are usually hard parts of an organism including shells, bones, teeth, woody trunk, stems, and branches.
