20 the cost of a hamburger is $2.50. each additional hamburger costs $1.00. sully wrote this explicit rule to explain the sequence of costs: f(n) = 1 + 2.5(n − 1). using this rule, he found the cost of 12 hamburgers to be $28.50. is this number correct? if not, identify sully's error.

$13.50

Step-by-step explanation:

Sully's error is the formula:

f(1)=2.5

f(2)=2.5+1

f(3)=2.5+1+1

f(4)=2.5+1+1+1

and so on...

So the formula should be:

f(n)=2.5+(n-1)

f(12)= 2.5+ 11 = 13.5

answer: y = 3/2 x - 3

y = 1/8 x - 3/4 that would be your correct option

step-by-step explanation: w

no because after the troops were pulled many blacks were killed by hangings lynchings and other cruel ways which in a way interrupted the reconstruction of the south and differed from the way abraham lincoln had an idea of reconstruction