Why did african american political participation rise and then suddenly decrease

Because of disenfranchisement

Explanation:

During the Reconstruction Era, African American gained the right to freedom and also the right to participate in politics, by voting or by being candidates. But after Reconstruction Era ended a series of laws and practices were created in the Southern States that were used to prevent African Americans from participating in politics or even voting, this process is called disenfranchisement. Some laws required literacy tests, others included poll taxes.

the amount of the purse is, $120.

tax rate =9%

first find the the total tax she paid on the amount is equal to the 9% of $120 i.e,

now,

total amount paid by shalika = $120 +$10.8 = $130.8