Diego is trying to lift a piano to the second floor of his house. Diego uses a pulley system and gives a big lift to the piano. The piano moves upward, then stops, and then it starts to fall to the ground. (The direction of the force of gravity is negative.)

nanotechnology is a powerful tool in biomaterials research as it creates numerous possibilities for the engineering of functional molecules. nano-bio refers to projected ability to incorporate biomimicry into various materials at nanoscale.  

i'm assuming that the correct answer is indeed the first one/ "a"..

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