Atwo dimensional figure made from two or more geometry figures

Refer to interactive solution 17.45 to review a method by which this problem can be solved. the fundamental frequencies of two air columns are the same. column a is open at both ends, while column b is open at only one end. the length of column a is 0.504 m. what is the length of column b?

How many sides does a regular polygon have if each exterior angle measure is 45 degrees explain your answer, i really don't understand this.

Kira looked through online census information to determine the overage number of people living in the homes in her city what is true about kira's data collection?