S.O.S. Mathematics CyberBoard

A person's productivity at a particular job may change with experience. Con-
sider the following model of effective labor input, L,

L=10(1-e^(-.1t))+2 e=2.71...

Where L is a measure of the "effective labor input" of a particular worker and t is
the worker's tenure (that ism years spent in a particular job). Use differentiation
to determine the marginal change in the effective labor input with respect to
time on the job, t. Provide a brief economic interpretation of the dierences in
these values of dL/dt.

please help me answer.

Let's start by taking the derivative of L.

I get:
dL/dt = e^(-.1t)