$1.$ Design a large building structure from the following list. For your design, show that it meets the ACI $318-19$ evaluation criteria for your choice of

a$.$ Floor slab

b$.$ Ground floor column

c$.$ Footing

d$.$ Retaining Wall

$2.$ Additionally, you wish to show your client the difference in design dimensions if only plain concrete is used $($no reinforcement$).$

$3.$ Design one example of plain concrete and one example of reinforced concrete structure for each of the four types listed in point $1.$

Note: The proposed Structure must be an Airport