Because their species is in danger of going extinct<span />
# moles = mass (g) / Mr (relative atomic mass)
# moles = 458 / ((23*2)+32+(16*4)
# moles= 458 / 142 = 3.2253521126760...
= 3.23 moles
They are combined 50% from your mom and the other from your dad
That answer for that question is B
