From 1962 until 1981 pennies were made from 95% copper and 5% zinc and had a mass of 3.1 g. Starting in 1982, pennies have been made from 97.5% zinc and 2.5% copper and have a mass of 2.5 g. Suppose you have a sample of pennies that consists of 46.7% pre-1982 pennies. Determine the average mass of a penny in this sample. Average mass =

Need asap question 1 minerals are organic compounds. true false question 2 what vitamin can be found in foods like oranges, grapefruits, and broccoli? a. vitamin a b. vitamin k c. vitamin c d. vitamin d question 3 what are minerals? a. chemical elements that are needed for body processes. b. organic compounds that the body needs in small amounts to function properly. c. small molecules used to build proteins. d. an organic compound that is insoluble in water and includes fats. question 4 how many types of vitamins does the human body need? a. 15 b. 11 c. 13 d. 17 question 5 vitamins are a good source of energy. true false

Balance the following reaction. as2s3 + 9o2 → 2as2o3 + so2

What is the chemical formula of magnesium bromide? a. mgbr2 b. mgbr c. mg2br2 d. mg2br