Helping verbs come before the main verb, the main verb in the sentence is repair therefor the helping verb would be could.
That's wave 'diffraction'.
Answer:
The acceleration of the car will be 
Explanation:
We have given that distance from stop sign s = 200 m
Time t = 0.2 sec
We have to find the constant acceleration
Now from second equation of motion 


So the acceleration of the car will be 
The most common metals used for permanent magnets are iron, nickel, cobalt and some alloys of rare earth metals