The water pressure at the bottom of 90N container is f = PS = 3000pa * 0.03m 2 = 90n.
70N plate is subjected to the pressure of the container, F=G =70N in total.
The pressure of 2333.3Pa wood subjected to container P = F/S = 70N/0.03 m 2 = 7000/3 pa is about 2333.3Pa.
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