Answer: A: The smoother the ramp surface, the greater the car's speed.
Explanation: I did the USA test prep
For the discovery of the elements polonium and radium. Prohibited from higher education in her native Poland (then controlled by Russia), she moved to Paris in 1891 and studied at the Sorbonne.
Yes, because they are in the same group also because they are similar with the <span>chemical properties</span>
Answer:
Isotopes are basically atoms of an element that have an unequal number of neutrons and protons. Of course the proton number remains the same, but the neutron number either decreases or increases, which leads to an overall change in mass. However, no chemical properties of the atom/element are changed as the electrons are the same number and do not react. In regards to Helium 4, the original number of neutrons in Helium is 2, and protons 2 as well. We see an equal number of neutrons and protons, hence an unchanged mass, and the element is <em>not</em> an isotope.
