问题如下：
Suppose that the annual profit of two firms, one an incumbent (Big Firm, X1) and the other a startup (Small Firm, X2), can be described with the following probability matrix:
What are the marginal distributions of the profits of each firm?
选项：
解释：
The marginal distributions are computed by summing across rows for Big Firm and down columns for Small Firm. They are
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