hello i have a prb with this exercice can any give me a hand

We must supply a prefabricated construction. These elements
be routed
the plant site by truck classic semi-trailer
the length of
loading is 13.5 meters. There are three types of items

• Elements of Type 1 with 5 linear feet
• Elements of Type 2 uses 4 linear feet
• Elements of Type 2 occupant 2.5 m linear

Any combination of elements can be transported in one truck:
for example,
can load a truck with two Type 1 and Type Element
3. Which occupies
2 * 5 +2.5 = 12.5 m linear. It then remains unoccupied one meter (rate
loading 92.5%). The
Plan loading of each truck may be different.
The volumes to be delivered to the site before it starts are
10 elements of type 1, 9
elements of type 2 and type 3 of 15 items.

How many trucks should be used to supply at least this site

1. Propose a heuristic to provide a good solution
this problem.
2. Propose a model of this problem to provide solution optimal form of linear program specifying the notation used, decision variables etc..