It is easier to climb up a slanted slope than a vertical slope

Yes it is easier to clime a gentle slope than a vertical or more steep slope. This is because gravity is always pulling objects down so when you climb upward gravity weighs you down, you have to use effort to move yourself in the opposite direction that gravity is pulling you that is why it is harder to climb up a slope. When you climb a gentle slope you still are using energy but it takes longer to reach the same height on a gentle slope versus a vertical slope. On a vertical slope you are climbing higher instead of farther so on each step gravity weighs you down much more than on a gentle slope. When climbing a gentle slope you don't rise as rapidly so gravity doesn't take as much of a toll on you and you have a chance to recover.