For the sake of clarity, I've written the page without the advertised ties; but you should be thinking of the accented note on the & of beat 5 this way, as a long note:
These are jazz exercises, so swing the 8th notes— you could also play them straight, for a modern/ECM type of feel. When doing that, you can play the triplets as written, or make an equivalent 16th note rhythm out of them. A new thing I've done with this POC is make some small changes in the ostinato; on a few of the exercises I've put in extra bass drum notes, in obvious places— they should be easy to make.
If you have any problem making the ostinato, you can start by playing it without the tie/rest, as follows:
Remember, once you've learned the whole page with your left hand on the snare drum, moving your LH around is a big value-multiplier for these exercises.
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