Making homemade ice cream is one of life's great pleasures. fresh milk and cream, sugar, and flavorings are churned in a bucket suspended in an ice–water mixture, the freezing point of which has been lowered by adding rock salt. one manufacturer of home ice cream freezers recommends adding 2.50 lb (1130 g) of rock salt (nacl) to 16.0 lb of ice (7250 g) in a 4-qt freezer. calculate the weight percent of nacl of the solution that will result when this mixture melts.

We know that weight percent can be calculated as

total weight = weight of NaCl + weight of water

weight of NaCl = 1130 g

weight of water = 7250 g

total weight = 1130 + 7250 = 8380g

Therefore

weight % of NaCl =

Thus weight % = 13.48 %

in scientific notation, the value of the  speed of light in a vacuum

  will be written as 2.995 * 10^8. when this value is represented in the form of

  a * 10^b, then, a = 2.995 and b = 8.

the value of the speed of light in a vacuum given above can also be rounded up to approximately 300000000. in this case, the scientific notation will be written as 3 *10^8.