I need help with the following:

If cell A1 is < L1, then the answer is cell A1, but

If cell A1 is K1 but < K2, then the answer is 100% of L1 plus 90% of (cell
A1-L1), but

If cell A1 is K2 but < K3, then the answer is 100% of L1 plus 90% of L2
plus 84% of (Cell A1-L1-L2), but

If cell A1 is K3, then the answer is 100% of L1 plus 90% of L2 plus 84% of
L3 plus 79% of (Cell A1-L1-L2-L3)


Cell A1 is the variable

K1=2400 L1=2400
K2=4000 L2=1600
k3=7143 L3=3143

How do I do this? I'm supposing I use nested IF functions, but I cannot get
it to work. I need this late tonight if at ALL possible. Thanks so much!

Lisa