Answer:
The sum rule is f' + g'
The difference rule is f' − g'
The product rule is f g' + f' g
The quotient rule is (f' g − g' f )/g2
Not sure
te rate is r
for decay, it is
A=P(1-r)^t
r=rate
P=present amount
dunno what b is
but I guess
A=28000(1-0.13)^t
A=28000(0.87)^t
I would guess the decay factor would be 0.87
