a student attaches a rope to the handle of a chest loaded with a few books while the other end of the rope is tied to spring scale. The student repeats the experiment with more book in the chest and records the data in a table. What can concluded from the data?

well in order to answer this question you have to provide more information < 3

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

since electrons are negative the answer is neagtaive