Write twelve cubed in exponential notation, expanded form, and standard form

Ihave a 69 and an 82. the 69 is worth 40% of my grade and the 82 is worth 15%. can someone tell me my current average grade.

Olga used 100 ounces of flour to make 225 muffins. how many ounces of flour will be used to make 300 muffins?

Mr.zimmerman invested $25,000 in an account that draws 1.4 interest, compouneded annually. what is the total value of the account after 15 years