Answer: 50.24 feet
Explanation:
Circumference of a circle is given by :-
, where d is the diameter of a circle.
Given : An architect is designing a circular opening 16 feet in diameter to make room for a spiral staircase.
i.e. d= 16 feet
Now, circumference of the circular opening will be :-
![C= (3.14) (16)=50.24\ \text{feet}](https://img.qammunity.org/2020/formulas/mathematics/middle-school/dhk8upc5zgns3zrxhyi5fu5rwc3mwwr4jg.png)
Hence, the circumference of the circular opening= 50.24 feet