What body system assists the respiratory system by pulling the rib cage down to allow air toflow in?

Diaphragm (a muscle)

Explanation:

the diaphragm moves the allows for more opening as it contracts down. It would most likely be the muacular system since the diaphragm is a muscle.

answer; /// i do believe that the correct answer is (c)nuclear bond

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