Answer:
Speed of the wreck after the collision is 65 km/h
Explanation:
When a car hits truck and sticks together, the  collision would be totally inelastic.  Since the both the vehicles  locked  together, they have the same final velocity.
Mass of car  
Mass of truck 
Initial speed of the car 
Initial speed  of the truck 
The final velocity of the wreck will be

since final speed are same, 


 
        
             
        
        
        
Answer: the minimal force that you need to apply to move the bureau is F = 198.45N
Explanation:
If you want to move an object, you need to apply a force that is bigger than the force of the statical friction.
The force of statical friction can be written as.
Ff = k*N
where k is the coefficient of static friction, in this case, k = 0.45, and N is the normal force between the object and the surface.
In this case, the normal force is the weight of the bedroom bureau, this is:
N = m*g = 45kg*9.8m/s^2 = 441N
Then the force is:
Fr = 0.45*441N = 198.45N
This means that the minimal force that you need to apply to move the bureau is F = 198.45N
and after this point, the force of friction will work wit the kinetic coefficient of friction, that usually is smaller than the statical one.
 
        
             
        
        
        
Answer:
3.486 km
Explanation:
Suppose Joe and Max's directions are perfectly perpendicular (east vs north). We can calculate their distance at the destinations using Pythagorean theorem:

where J = 0.5 km and M= 3.45 km are the distances between Joe and Max to their original parting point, respectively. s is the distance between them.
