The cubic foot is a unit of volume in the imperial unit system with the symbol ft³.
1 cubic foot is equal to 1/27 yd³ or 1728 in³. It is equal to the volume of a cube measuring 1ft on each side.
One cubic foot of water weighs 62.4 lbs or 28.29 kg.
The tablespoon is a unit of volume in the US customary system and uses the symbol Tbsp.
In the kitchen, the tablespoon is the larger of the commonly used spoons served at the table and represents 1/2 US fluid ounce or, expressed in SI / metric format; 14.78676 ml.
This is often expressed as equivalent to 3 teaspoons (3 Tsp) although strictly speaking it is a little under the size of 3 metric teaspoons (5 ml) at 4.92892159375 ml. It was established to assist normal kitchens with recipes without the need for specific measuring equipment or devices. Although many spoons differ in sizes (and very rarely is a spoon filled accurately) it allowed for a decent "catch-all" and gave a "good enough" result most of the time.