10. Which arrow or arrows represent reactions that demonstrate a conservation of mass and energy? Explain your answer.

odds are decent that your handwriting right now looks a little bit different than it did five years ago, and will look different again in five more. when i look back through my notebooks from middle school to now, i see a long, slow progression from meticulous and teeny letters to bigger, sloppier ones, plus a few side detours: sometime in high school, for example, i decided those loopy cursive lowercase f’s were just the coolest, adopting them as the lone rep for cursive in my otherwise all-print handwriting.

explanation:

a:

by the combination of an unlimited number of elements

the answer is barium and copper bromide