9. Find a least squares solution given the following information. Then determine the least-squares error. Round your least-squares error to four decimal places. Do not use the command LeastSquare[ ]. A= [2 0 1 1 1 -3 4 1 1 0 -1 -3] b = 8 0

Assume that a license plate must be of length 7.  How many different license plates are possible               (a)  if it can only contain capital letters?               (b)  if it can only contain capital letters, and repetition of letters isn’t allowed?               (c)  if it can contain capital letters or the digits 0-9, repetition isn’t allowed, and the plate must begin with the letter “R”?

How many numbers from 1-999 have: 1) all three digits the same? (assume that "1" is represented as "001" for this exercise) 2) exactly two digits the same? (assume that "1" is represented as "001" for this exercise)

Please answer the question with steps and details… As soon as you can, Thank you Discrete Mathematics