The phrase "the iron curtain" is associated with what era of history?

The phrase "The Iron Curtain" is associated with the Cold War and it refers to the closed nature of the Soviet Union. It evokes the invisible boundary line that separated Eastern and Western Europe after the end of WWII until the end of the Cold War in 1991.

Explanation:

The Iron Curtain refers to the divisions between East and West after WWII when the Soviet Union made efforts to block itself and all its satellite states off from Western influence. There were military alliances developed on the Eastern side of the Iron Curtain with the Warsaw Pact and on the Western side with NATO. There were some physical manifestations of the border or divide between East and West, the most symbolic being the Berlin Wall.

the median of the data is 4.

step-by-step explanation:

the median means the middle number of a given number.

to decide which one is the median, arrange in ascending or descending order. but sometimes, you may find two(2) number in the middle, but it's easy, just add them together and divide by 2.

so,   determine the median of the data. 2, 3, 3, 4, 5, 7, 9

it is already arranged, count 3 times forward and 3 backward and the one left is your answer.

2,3,3,4,5,7,9

our answer is 4.

hope this !