Question

1. add in the missing forces so the box will be balanced.

5n
5n
25n

Explanation:

Step1: Analyze horizontal forces

For horizontal balance, the left - ward force ($F_{left}$) should equal the right - ward force ($F_{right}$). Given $F_{right}=25N$, so $F_{left} = 25N$.

Step2: Analyze vertical forces

The sum of downward forces: $F_{down}=5N + 5N=10N$. For vertical balance, the upward force ($F_{up}$) should equal the downward force. So $F_{up}=10N$.

Answer:

Horizontal left - ward force: $25N$; Vertical upward force: $10N$