PLEASE HELP ME WITH THIS ONE QUESTION

Answer:
[tex]^{214} _{83} Bi[/tex] → [tex]^{210}_{81}Tl[/tex] + [tex]^4_2He[/tex]
Explanation:
[tex]^{214} _{83} Bi[/tex] → [tex]x[/tex] + [tex]^4_2He[/tex]
Subtract the [tex]^4_2He[/tex] from the [tex]^{214} _{83} Bi[/tex]
214 - 4 = 210
83 -2 = 81
Therefore, [tex]x[/tex] = [tex]^{210}_{81}Tl[/tex]