Plz help!! find the area of the composite figure below

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In triangle △abc, ∠abc=90°, bh is an altitude. find the missing lengths. ah=4 and hc=1, find bh.

Florence price's brownies and more sells all types of cookies and pastries. on tuesdays, they markdown all brownies 75% to a sale of $1.50 a dozen. find the selling price and the markdown of a dozen brownies.