Six have income ceilings, with five different formulas for the limits, in each case involving two phase-out schedules, one for single filers and one for joint filers.
Strength: This phase, which requires similar form to the balance phase, including walking lunges, hamstring curls and single-knee squats with toes raised.
For starters, the Russians will surely try to lock us into a "first phase NMD" along the lines of the single, ground-based site President Clinton ultimately chose not to start building in Alaska.