John Maynard Keynes first:

discussed the uncertainty principle.

made early discoveries in psychoanalysis.

warned that democracy was a threat to the achievements of western society.

was positive that laissez-faire capitalism would survive forever.

urged government to stimulate the economy by increasing the money supply.

I would go with the last choice

Explanation:

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 !

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