At first glance, the push jerks appear to be the place where most time is spent. However, the machine and double-unders will add up quickly. Don't let that hold you back from pushing on the barbell. The weight should be something you could easily do all 10 reps unbroken when fresh. During the AMRAP, try not to split it up more than once. For the double-unders and machine, pick a medium pace from the start, and hold it across the 15 minutes. Try and stay at that 70-80% range.