How many days of cross training should I do a week?

I have been doing the following:
1. Fitness runs on Monday, Tuesday, Thursday, and Friday. (40-60 minutes comfortable)
2. Strength run on Wednesday. (10-15 minute tempo w/ one mile warm up and cool down)
3. Endurance run on Sunday. (60-90 minutes comfortable)
4. What I call cross training on Saturday (bike or swim for 30 minutes)

Should I be doing more cross training or different kinds of cross training? What has helped to run your fastest times once you got onto the track in the spring? I run the 800m, 1500m, and 3000m, not in any particular order.

Swimming for cross country training?

My coach told me to run 15-30 minutes during the summer for cross country training…but I want to do something besides just running (like swimming). How much would I have to swim to excercise my legs as much as running and what should I do while swimming? I don’t have a very large pool and it is oddly shaped so laps would not be very helpful. Thank you.

is a hill work out a good cross-training exercise while training for a marathon?

and i mean running up and down the same hill for like 30 minutes or for so many reps
the first 2 answers are stupid. i don’t want your opinion on how to run. i want to know if hill training is a good cross training exercise for the marathon!!