Why did Southern states secede after Abraham Lincoln was elected
president?

i think d.

Explanation:

let me know if this is incorrect

it was made because he wanted to try to make people convert as well people who would have read or studied this item at the time it was created were probably people who wanted to change religions who thought conversion was a good idea.

angle a = 40.6°

step-by-step explanation:

for any right angle triangle we know the pythagoras theorem reveals

hypotenuse² = height²+base²

by this formula we will calculate the length of hypotenuse

h² = 6²+7²

⇒ h =√36+49 = √85 = 9.22

now from the given triangle sin a = height/ hypotenuse

                                                sin a = 6/9.22 = 0.651

therefore

so angle a = 40.6°