Francis Sumner is considered to be the father of African American physchology.
Each of these ODEs is linear and homogeneous with constant coefficients, so we only need to find the roots to their respective characteristic equations.
(a) The characteristic equation for

is

which arises from the ansatz
.
The characteristic roots are
and
. Then the general solution is

where
are arbitrary constants.
(b) The characteristic equation here is

with a root at
of multiplicity 2. Then the general solution is

(c) The characteristic equation is

with roots at
, where
. Then the general solution is

Recall Euler's identity,

Then we can rewrite the solution as

or even more simply as

Might not be a great answer but:
Due to the 3/5 clause, each slave was counted as 3/5 of a person represented in congress. The south's political power relied largely on this fact.
D) selecting random sample allows for a more representative sample in a survey.