(2^8 * 5^-5 * 19^0)^-2 *(5^-2/2^3)^4 * 2^28 (please include answer and simple steps asap! thank you!)

The weight of an object in the water is 7% of its weight out of the water. what is the weight of a 652g object in the water?

If wxyz is a square, which statements must be true? plz < 3

The floor of a building consists of 3000 tiles which are rhombus shaped and each of it's diagonals are 45 cm and 30 cm in length. find the total cost of polishing the floor, if the cost per m² is rs. 4.