I have a plasmid with a concentration of 12858 ng/μl then I did serial 1/10 dilutions. I used my leas concentration DNA(1.28*10^-6 μg/μl). Then I took 5μl of that and added it to a tube with 25μl of competent cells. After transformation, I added 500 μl S.O.C. Total vol 530μl.

Then I did serial 1/10 dilutions to 5 tubes with a total vol of 200μl. I add 180μl S.O.C to all 5 tubes and then I add 20μl of 530μl into the first tube and then I took 20μl of that and adding to the second. I did the same until the last tub. Then I spread 50 μl of the last three dilutions of the transformation mixture onto LB plates with antibiotics. The day after I count the number of colonies. The last tub gives 300 colonies, fourth tube1071 colonies grow.

Now I should know the mass of DNA to find TE.

could you please help me? I am confused and I don't know what should I do.