I have a question using R Please help We generate a nxk matr

I have a question using R. Please help!

We generate a nxk matrix M and a vector V of length k for some specific values of n and k as follows; Now, carefully review the following for loop. Rewrite the code that does the same job but doesn\'t use a for loop. Now do the same experiment for n = 400 and k = 500. Which code runs faster, your code or the for loop? Demonstrate that using function system.time().