If f(a)=2a, what is the value of (f(a-b)+f(a))/b ?  Choose one:
A) 4a/b	B) 3a+4b/b	C) (4a-2b)/b	D) 5a-6b*b	E) 8a-7b/b
f(a)=2a   f(a-b)= 2(a-b)   (f(a-b)+f(a))/b = (2(a-b)+2a)/b = (4a-2b)/b   Answer is (4a-2b)/b
<result>C</result>
If f(a)=2a, what is the value of (f(a-b)+f(a))/b ?