Answer:
Archimedes went to sleep 7.51 meters from the rock.
Step-by-step explanation:
We are told that the sunlight reaches the ground at an angle of 43°, and that the rock is 7 meters tall.
The distance [tex]d[/tex] from the rock where Archimedes should sleep is:
[tex]tan (43)=\frac{7}{d}[/tex]
[tex]d=\frac{7}{tan(43)} =\boxed{7.51\:meters}[/tex]