Answer:
The base is 9.4 milliliters
Explanation:
First, you would notice that they give you the perimeter of it. Meaning 51.4 was a sum of adding the height and base length twice. So you would take 51.4 and subtract 16*2 from it. Which would be 19.4. Next, since 19.4 would be both bases added, and they are both the same, you would do 19.4/2=9.4
The base is 9.4 milliliters.