Answer:
The wavelength is 
Explanation:
From the question we are told that
The wavelength of the red laser is 
The spacing between the fringe is 
The spacing between the fringe for smaller laser point is 
Generally the spacing between the fringe is mathematically represented as

Here
is the distance to the screen
and d is the distance of the slit separation
Now for both laser red light light and small laser point D and d are same for this experiment
So

=> 
Where
is the wavelength produced by the small laser pointer
So

=> 
KE= (1/2) mv²
So, the variables we need to include in our question would be a varable for a mass(m) of an object at some velocity(v).
My Answer:
(This is just an example question, yours can be different)
What is the Kinetic Energy experienced by an bouncy ball rolling at 7m/s (that's your velocity) across a frictionless surface that has a mass(m) of 10 grams?
Answer:
2.93 m (which agrees with answer "C" on the list)
Explanation:
Recall that the speed of the wave equals the product of the wave's length times its frequency. Therefore, the wavelength is going to be the quotient of the speed of the signal divided its frequency:
Wavelength = 2.997 10^8 / 1.023 10^8 = 2.93 m