What is 2.04905820850285 in scientific notation

The value of the expression 16-^3/4 8 1/8 -6 6 1/40 1/64

The length of a rectangular board is 3 feet less than twice its width. a second rectangular board is such that each of its dimensions is the reciprocal of the corresponding dimensions of the first rectangular board. if the perimeter of the second board is one-fifth the perimeter of the first, what is the perimeter of the first rectangular board?

20 points - ! gia decides to buy square tiles to cover her kitchen floor. the tiles are 18” square tiles and cost $3.85 each. how much will it cost to tile her kitchen if the measurements are 11’ x 12’?