Answer:
 Distance traveled in third second = 25 meter.
Step-by-step explanation:
 We have equation of motion, 
, s is the displacement, u is the initial velocity, a is the acceleration and t is the time.
 During the first second it travels 5.0 meters
 In this case u = 0 m/s, t = 1 second and s = 5 meters
 Substituting
 

 Now we need to find how much distance it travel during third second.
 Distance traveled in third second = Distance covered in 3 seconds - Distance covered in 2 seconds
 Distance covered in 3 seconds = 

 Distance covered in 2 seconds = 

 Distance traveled in third second = 45 - 20 = 25 meter