Please help me with this answer thank you

What is the number 321,000,000 in scientific notation? also what is the number? ?

Alana has 12.5 cups of flour with which she is baking four loaves of raisin bread and one large pretzel. the pretzel requires 2.5 cups of flour to make. how much flour is in each loaf of raisin bread? explain the steps to follow to get the answer.

If chord ab is congruent to chord cd, then what must be true about ef and eg?