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List the elements of the set in roster notation. (enter empty or ∅ for the empty set.) {x | x is a letter in the word hippopotamus}

After applying the composition r0.90 ry to rs what are the coordinates of r' and s'? a.r'(–3, 1),  s'(–3, 5)b.r'(–1, 3),  s'(–5, 3)c.r'(1, 3),  s'(5, 3)d.r'(5, 3),  s'(1, 3)

Joseph haydn pet store offers wide variety of leashes for dogs. the store purchases one popular type of leash from its manufacturer for $4.38 each. joseph haydn pets marks up leashes at a rate of 238% of cost. what is the retail price of the popular leash?