Classify the following hikes in terms of difficulty: Half dome in Yosemite, Mt Everest in Nepal, Mission Peak in California
Mt Everest is the toughest among the list based on scaling height of 28k feet and requires multiple days of hike, acclimatization at different altitudes, requires carrying oxygen tanks and heavy gear.

Half-dome is also considered as a difficult hike but less tougher than Mt Everest. Half-dome can be done as a day-hike and is at 4k elevation gain from the Yosemite valley and with moderate fitness & stamina its possible to do.

Mission Peak is considered a medium difficulty hike. It takes between 2-3 hours to scale Mission peak, it can be strenuous for people with health difficulties and less stamina.