Please please help me (the number in the photo is 20 and then the letter is x)

(also if you can pls go to my profile and answer the question underneath this one)

Organisms that live in the alpine and taiga biomes have developed unique adaptations that aid in their survival. the douglas-fir is a conifer tree that grows in the taiga biome. it has an average height of about 70 feet, and its wood is an important source of lumber.

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?

At $1.32 million, they closed last month percent above what they paid in 2007." how much did they pay in 2007?