The notes with all black are 1 beat (first position for tuba idk about the rest) the line things are pauses so you would pauses for like 1.99 seconds
There are 87 girls and 58 boys!
i divided 5 from 145 and got 29.
i multiplied 29 and 3 and got 87.
87 is the girls total.
then subtracted 87 from 145 and got 58.
58 is the boys total.
hope this helps!
Exceseuor if im wrong sorry