Does anyone know how to prove this?

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

Sara has been reading about different types of financial grants, including federal pell grants, academic competitiveness grants, smart grants, and teach grants. which statement about these grants is true? filling out a fafsa will not her apply for these grants. she will not have to pay back any funds she receives from these grants. these grants only go to students with less than a 3.0 gpa. she will have to pay back all the funds she receives from these grants.

Complete the equation of the live through (-1,6) (7,-2)