Company XYZ conducts a field experiment to see the impact of in-store special display on sales under the following conditions:

1) All the stores are randomly assigned to one of the two groups, say G1 and G2;

2) The stores in G1 have in-store special display and those in G2 do not have it

2) In-store special display for G1 happens between week 1 and week2

and lasts throughout the week 2

3) Weekly sales of G1 and G2 are in the following table

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