Which of the following is an example of a ball of clay undergoing a physical change? I. The ball is thrown into the air
II. The ball is broken into two separate halves
lll. The ball is rolled along the ground
lV. The ball is flattened into a pancake like shape

The content of manganese (mn) in steel was determined spectrophotometrically and with the use of the standard addition method. an unknown sample of mn from a digested steel sample gave an absorbance of 0.185 when analyzed spectrophotometrically. when 5.00 ml of solution containing 95.5 ppm mn was added to 50.0 ml of the unknown steel solution (digested sample), the absorbance was 0.248. calculate the concentration, in parts-per-million (ppm), of mn in the digested steel sample solution.