Answer:
The distance is 
Explanation:
From the question we are told that
The wavelength of the light source is 
The distance from a pin hole is 
The diameter of the pin hole is 
Generally the distance which the light source need to be in order for their diffraction patterns to be resolved by Rayleigh's criterion is
mathematically represented as

substituting values


There are two force acting on an object that is being lifted. (1) the weight of the car, (2) the upward force. The difference of these force should be equal to the product of the mass and the acceleration. (This is the content of Newton's 2nd Law of Motion). If we let the lifting force be F,
F - (830)(9.8) = (830)(3.8)
The value of F from the equation is 11288 N.
Because they have different measurements and weight and mass and some measurements are the same
let the distance of pillar is "r" from one end of the slab
So here net torque must be balance with respect to pillar to be in balanced state
So here we will have

here we know that
mg = 19600 N
Mg = 400,000 N
L = 20 m
from above equation we have



so pillar is at distance 10.098 m from one end of the slab