Accelerating at 9.8 m/s² means that every second, the speed is 9.8 m/s faster than it was a second earlier.  It's not important to the problem, but this number (9.8) happens to be the acceleration of gravity on Earth.
1% of the speed of light = (300,000,000 m/s) / 100 = 3,000,000 m/s .
Starting from zero speed, moving (9.8 m/s) faster every second,
how long does it take to reach  3,000,000 m/s ?
           (3,000,000 m/s) / (9.8 m/s²)  =  306,122 seconds .
                                                   (That's  5,102 minutes.)
                                                        (That's  85 hours.)
                                                     (That's  3.54 days.) 
Speed at the beginning . . . zero .
Speed at the end . . . 3,000,000 m/s
Average speed . . . . . 1,500,000 m/s
Distance = (average speed) x (time)
               = (1,500,000 m/s) x (306,122 sec) = 4.592 x 10¹¹ meters
                                                                     =  459 million kilometers
                         That's like from Earth 
                                                  to       Sun
                                                             to    Earth
                                                                    to        Sun.  
        
             
        
        
        
Speed=distance/time, rearranging gives speed*time=distance therefore the first section of the journey yielded a total distance of 40km, the second journey was stated to be 20km which was completed in (20/30)*60=40minutes. Therefore the total journey was 60km which was completed in 1hr40 minutes so the average speed was (60/1.66..)=36km/h.
        
             
        
        
        
 BEHAVIOURISM holds the belief that scientific psychology should be studying only obserrvable behaviors. The underlying principle of behaviourism is that behavior is influenced by our interaction with the environment and has little to do with factors internal to us. From which follows the assumption that when we are born, our mind is a blank slate
 
        
                    
             
        
        
        
Answer:
Because it unites particle and wave nature.
Explanation:
De Broglie wavelength can be defined as the,

Here, h is planks constant, m is the mass of electron, v is the velocity of electron.
Since the de Broglie wavelength can behave like the photon wavelength with respect to the  momentum
It unites particles and waves nature ,so De Broglie wavelengths is probability waves associated with the wave function according to physicists.