Isotopes are variants of a particular chemical element which differ in neutron number (neutral particle)and all isotopes of a given element have the same number of protons (positive particle) in each atom.So isotope B of the sodium will have 11 protons, 11 electrons but it may have a wide range in its number of neutrons.
Option C would be correct. The organ system can plays many parts at one time. Also, it is the only system listed.
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Answer:
b
Explanation:
because an object is in motion continues in motion with the same speed and in the same direction unless acted upon by an unbalanced force.