Answer:
25.2 km east
Explanation:
The relationship between velocity and displacement is given by:

where
v is the velocity
d is the displacement
t is the time
In this problem, we have:
east is Rebecca's velocity
is the time taken
Re-arranging the equation, we can find Rebecca's displacement:

and the direction is same as velocity (east)
<span> The short answer is that they are not always weaker in fact. Some ionic compounds have very strong bonds, while some covalent bonds are quite weak. Usually however, it is easier to break an ionic bond than a covalent one. What determines the actual strength of a bond is quite complex, but let me try to explain the basic principles. this is the best answer i can come up with</span>