We will convert the 1dm3 in terms of cm3 as follows:
1dm^3 = (10 cm)^3 = 1000 cm^3
The mass of platinum is equal to 900 lb. Then we will convert the mass in terms of grams as follows: 1 lb = 453.6 g 900 = 900 x 453.6 g = 408240 g
Then density of platinum is equal to 21.4 g/cm^3 We will calculate the volume of platinum in mass 408240 g as follows: Volume of platinum = mass of platinum / density of platinum = 408240 g / 21.4 g/cm^3 = 19076.6 cm^3
The total volume of platinum is 19076.6 cm^3 The volume of platinum in 1 L bar is 1000cm^3 So, to calculate the number of bars we will use the formula as follows; Number of bars = volume of platinum available / volume of platinum required in 1 L bar = 19076.6 cm^3 / 1000 cm^3 = 19 So, the number of bars are 19.
Objects in free fall, disregarding terminal velocity, accelerate at 9.8(m/s)/s. so for every second it was falling, it gained 9.8m/s in speed. 9.8 * 10 = 98m/s