Mr. chen bought 3 pound of ham for $21. at this rate how much would 9 of ham cost

Can someone tell me if this is perpendicular? !

Which net represents the pyramid below? meh

Which elements in the set are integers? –8, 3⁄4, √ 18 , 0, √ 16 , 5, –2⁄7, 6 a. –8, 0, 5, 6 b. –8, 0, √ 16 , 5, 6 c. 3⁄4, √ 18 , √ 16 , 5, –2⁄7 d. –8, 0, √ 18 , 5, 6