Just finished the White Mountain Double. The climb from the Owens River to Schulman Grove is 20 miles. You gain 6000'. Average grade is 5.58%, but that takes into account a flat portion leading into the Schulman Grove turnoff, a short downhill just after the turnoff, and some flat/rollers for about a mile after mile 15.
Ride hills, more hills and even more hills.
Don't know about the other climbs.