Q1: Long easy run: No more than 25% of your weekly mileage. Be sure you can hold a conversation while you’re running. If you can’t, you’re running too fast. Purpose: Overall cardiovascular health and efficiency and musculoskeletal strength.
Q2: Option 1: Cruise Intervals (Purpose: endurance building particularly for marathoners). Option 2: Hill repeats (Purpose: Power and strength building).
Q3: Tempo: 1-2 miles warm-up. Striders. Then a 30-minute run at a “comfortably hard” pace. Carrying a conversation would be difficult or not doable. Warmdown: Easy 1-2 miles. If you’re using your VDOT score, go about 10 seconds per mile slower than your T pace. Purpose of the workout: Retaining or building endurance.