Why are equations like w - x + x = w called identities?

"princess tower" in dubai is considered the world's tallest residential building, towering to 1 0 1 101 floors! t ( n ) t(n) models the number of tenants living on floor n n of the tower. what does the statement t ( 2 0 ) = t ( c ) t(20)=t(c) mean?

43lbs of tomatos cost $387. how much would 41lbs cost

Abakery recorded the number of muffins and bagels it sold for a seven day period. for the data presented, what does the value of 51 summarize? a) mean of bagels b) mean of muffins c) range of bagels d) range of muffins sample # 1 2 3 4 5 6 7 muffins 61 20 32 58 62 61 56 bagels 34 45 43 42 46 72 75