INSTRUCTIONS: Write the optimization model for the following problems.

Clearly define the notation of the sets and parameters, the decision variables, the

objective function and constraints.

a$)$ Transportation Problem with various means of transportation:

$-$ Consider the existence of several means of transportation available to ship

products from factories to customers. Enter the set k to represent

these different types of transport.

b$)$ Transportation problem with various types of products:

$-$ Assume the existence of several types of products that customers request and that the

factories can produce. Define the set p to represent these different types of

products.

c$.$ Transportation problem that considers both previous aspects:

$-$ Consider the situations described in points $($a$)$ and $($b$),$ where both the various

means of transportation as the different types of products are present in the

transportation process.