Sentence:  ( 1 ) As far down as 400 miles below the surface the material should be <WSD>hot</WSD> enough to be plastic and adjust itself to twisting forces by sluggish flow rather than by breaking , as rigid surface rocks do . 
Meaning of the word marked with <WSD> tags:  used of physical heat; having a high or higher than desirable temperature or giving off heat or feeling or causing a sensation of heat or burning