What energy transformation occur in a hot air balloon A. kinetic>mechanical>light

B. mechanical>sound>electrical

C. chemical>thermal>kinetic

D. chemical>electrical>mechanica l

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

answer:

technetium is the most reactive. this is followed by silver. the least reactive out of these three elements is strontium.