What is not an efficient greenhouse gas : helium methane CO2 or water vapor

How many solutions are there to an inequality

What is 2^2+2^2?!

Comparing 700 and 70

Negetive 3 is less than 3x equal to 9

Suppose that a diamond weighs 0.0182 carat. What is that number in expanded form

A perfect square is the square of an integer. Of the integers from 2 through 99, how many have at least one perfect square factor > 1?

0.2 with an exponent of 4

Marco is selling floral arrangements. Each arrangement uses 1 vase and 11 orchids. Each case cost Marco $4.00. Let C be the total cost of the arrangement and r be the cost of 1 orchid. Which equation should Marco use to find the total cost A.

Ken's contest entry, why honesty is important must be 100 words or less. Ken gets about six words on one line of his notebook paper. About how many lines can he write without going over the 100 word limit.

Lin bought 3 hats for $22.50. At this rate, how many hats could she buy with $60.00?