Answer: Hello there!
a) the time signature is 4/4, you can see it at the start of the partiture, this means that you have 4 beats per bar.
b) the sixth measure has a black note (one beat) and a white note (two beats) so this measure only has 3 beats.
c) in the measure you only have 3 beats, and the time signature is 4/4, then you need to add another beat, you can add for example a black note.
d) before the half rest you have two black notes, then you have 2 beats, this mean that the rest need to be for the other 2 beats.
e) If a black note is equivalent to a beat, then here you have 4 notes in a beat, and each one is equidistant, so each one has 1/4 of a beat.
f) the two dots are a repeat sign, which means that at that point you start from the begginig, (only one time).
There is another notation where you have two times this notation enclosing some measures, this means that you only repeat the enclossed measures.
