I need help with 63 I included 61 to help with it!!

Facial shaving brushes are either bulb-shaped or fan-shaped. an experiment is to be conducted to determine whether the lather thickness is the same for both types of shaving brushes. in previous studies, it was determined that shaving brush size (small, medium, large) is associated with lather thickness, but shaving brush type (wolf whiskers, maggard razors, frank shaving, and so on) is not associated with lather thickness. how could the experiment best be conducted? by blocking on shaving brush size by blocking on shaving brush type by blocking on shaving brush shape by blocking on lather thickness without blocking

12. identify the main term from the following statement: arthrotomy of toe, interphalangeal joint

Ascientist has predicted that the population of earth will continue to grow exponentially until the year 2300. at that point, we will reach carrying capacity of earth’s resources, and population growth will plateau. if the scientist’s prediction is correct, what can you predict about human energy use at that time? justify your answer by explaining the relationship between population growth and energy use. (5 points)