Which of the following is a variable gas in our atmosphere

a.
argon

b.
oxygen

c.
nitrogen

d.
water vapor

e.
all of the above are correct

Here is a picture  of the net. its 4 squares in a row diagonal and on the third draw one square aove and under

Amath expression is a collection of one or more terms, which are separated by the signs ( + , - , x , / ).example :   8+b8+b  or  a−3a−3in algebra, an equation is a mathematical statement with two expressions where, each expression is separated by an equal (=) sign. variables can be present on both the sides of the equality (=) sign and we use letters to denote such variables.example 1:   x=4+2x=4+2  , [here, we can observe that the variable is present only on one side of the equation].example 2:   2x+3=x+42x+3=x+4  , [here, we can observe that the variables are present on both side of the equation].

Answerwide-open;