Can someone tell me the answer plz plz I’ll give you brainlist and points plz This is my final test No wrong answers

The valence electrons

Explanation:

The valence electrons determine an element's properties because chemical properties of each element are determined by the element's electronic configuration and PARTICULARLY by its outermost valence electrons. I hope it helps!

                      ~Good luck

6.4 cm (max) - 25 cm (min)

so here we go

atomic mass

239 + 1 = y + 134 + 3 combine like terms

240 = y + 137             subtract 137 from both terms

240 - 137 = y

103 = y

atomic number

94 = z +54 + 0

94 = z + 54               subtract 54 from both sides.

40 = z

answer