Umm_help me_plz_plz mean please for u know what ppl_not explaining ppl

The description of the house in this excerpt gives an example of

Which of the following is an element of plot

Ead this sentence from the evolution of useful things. the underlined phrases indicateaaking waterproof sandpaper would allow wet sanding, which in turn would cut down on dust, and thus be a greatmprovementpassing of timea directional change of positiona cause-and-effect relationshipsequence of events. save and exitmark this and retur