Notice by the time signature at the beginning that Amazing Grace is in 3/4 time. That means there are 3 beats in each measure. The number
on top in the time signature tells you how many beats in a measure. The bottom number indicates the type of note that receives one beat (a quarter note).
This arrangement plays through the song twice -- once on the lower notes and once on the higher notes. You can
play it either way, or both if you prefer.