Answer:
lithium
Explanation:
A lithium atom contains 3 protons in its nucleus irrespective of the number of neutrons or electrons. Notice that because the lithium atom always has 3 protons, the atomic number for lithium is always 3. The mass number, however, is 6 in the isotope with 3 neutrons, and 7 in the isotope with 4 neutrons.
Kinetic energy= 1/2 m v^2
so... 1/2(1350)(12^2)
kinetic energy = 97200Joules
A (b) would be 42 (c) from x to Y mark me as brainlist thanks
