The answers are:
“colored persons then possessed the elective franchise”
“that it was made exclusively for the white race is . . . contradicted by its opening declaration”
“free colored persons were then citizens of at least five States”
In the excerpt from "Dissenting opinion on Dred Scott v. Sandford, " the author Justice Benjamin Curtis does not agree with the thought that the American Constitution was made exclusively for and by white people only. He acknowledges that there were at least five states in which black people already had the right to vote at the time the Constitution was written.