If this is asking for written word then
Twelve times f plus Twenty-four.
B) 1.339 x 10^6 gallons. When you add 812,000 to 527,000 you get 1,339,000, and to write that in scientific notation you need to make the number less than 10 and more than 1, which is 1.339 and to get the 1,339,000 you need to multiply 1.339 by 10^6.
1500000000000 in scientific notation is
1.5 * 10^12
That is because you move the decimal point 12 places to the left for it to become 1.5.
1.5 * 10^12
move the decimal point 12 places to the right and you got the original number, 1500000000000.
Hope this helps!