answer:There are 100 lines of data. The number of times each sign appears in each line is: + - = 48 25 27 26 25 19 27 20 23 13 22 15 24 24 16 17 15 18 20 20 12 18 21 11 28 16 26 16 16 18 19 20 19 16 22 14 18 27 5 19 16 15 15 21 14 19 16 15 17 20 13 26 20 16 17 21 12 22 17 15 22 14 20 13 20 17 10 10 14 20 26 16 22 25 14 30 10 10 16 17 17 21 12 17 24 17 22 16 25 18 22 21 7 26 20 14 16 23 11 22 12 16 12 23 18 23 12 15 16 23 11 11 17 22 17 21 12 23 17 10 20 21 9 18 22 10 15 19 16 22 19 9 19 19 12 25 11 14 13 24 13 22 18 10 19 18 13 17 18 15 20 18 13 16 24 10 24 17 9 23 18 9 20 20 10 23 15 12 16 23 11 22 15 13 16 26 8 24 17 9 22 21 7 21 19 10 20 19 11 18 19 13 12 20 18 24 16 10 18 20 12 22 14 14 12 23 15 17 19 14 16 22 12 24 19 7 18 26 6 21 19 10 22 19 9 20 19 11 19 14 17 20 25 5 22 19 9 25 14 11 17 22 11 16 22 12 20 18 12 21 17 12 28 13 9 15 22 13 20 20 10 21 16 13 20 20 10 24 16 10 26 17 7 17 25 8 14 22 14 16 23 11 13 24 13 16 24 10 19 19 12 19 20 11 19 21 10 24 19 7 16 26 8 22 17 11 17 16 17 24 17 9 15 20 15 22 20 8 18 21 11 13 22 15 24 15 11 22 20 8 16 25 9 21 22 7 22 17 11 15 23 12 24 12 14 16 23 11 22 14 14 17 24 9 18 21 11 18 22 10 20 21 9 18 21 11 16 22 12 19 17 14 23 18 9 14 23 13 22 18 10 21 13 16 23 21 6 22 18 10 23 22 5 19 23 8 23 16 11 26 13 11 20 20 10 21 18 11 20 17 13 23 18 9 21 23 6 23 12 15 19 23 8 23 18 9 18 23 9 23 12 15 17 23 10 22 20 8 21 20 9 24 17 9 17 21 12 22 19 9 29 14 7 20 19 11 22 14 14 22 18 10 24 16 10 22 21 7 20 16 14 17 22 11 19 17 14 24 20 6 22 18 10 27 8 15 18 25 7 19 20 11 22 14 14 16 24 10 20 22 8 23 18 9 17 26 7 21 17 12 17 20 13 15 26 9 16 23 11 14 26 10 22 18 10 21 16 13 24 20 6 14 25 11 24 17 9 17 25 8 23 17 10 21 20 9 22 19 9 28 10 12 21 18 11 15 24 11 22 18 10 14 21 15 18 22 10 24 17 9 17 16 17 20 17 13 27 15 8 12 27 11 20 21 9 20 17 13 24 14 12 25 14 11 23 16 11 15 25 10 25 17 8 24 18 8 24 17 9 21 18 11 21 18 11 22 18 10 21 15 14 18 22 10 22 19 9 19 23 8 19 20 11 22 19 9 19 19 12 19 23 8 23 21 6 24 16 10 23 18 9 20 23 7 18 16 16 18 22 10 23 20 7 17 23 10 21 17 12 17 22 11 18 24 8 18 20 12 21 20 9 15 25 10 23 18 9 20 18 12 25 18 7 19 23 8 22 20 8 16 25 9 23 18 9 19 23 8 23 21 6 19 23 8 23 18 9 24 16 10 19 21 10 22 15 13 21 17 12 20 19 11 20 18 12 19 23 8 20 20 10 19 22 9 20 19 11 21 18 11 19 24 7 22 17 11 22 20 8 25 17 8 17 20 13 16 25 9 22 20 8 21 20 9 27 11 12 21 18 11 21 18 11 19 21 10 19 26 5 19 20 11 19 22 9 18 20 12 21 20 9 19 24 7 22 17 11 19 22 9 19 22 9 20 18 12 20 20 10 19 22 9 21 16 13 18 20 12 17 21 12 21 20 9 22 15 13 20 21 9 18 22 10 25 16 9 24 18 8 23 15 12 18 23 9 26 13 11 20 23 7 23 18 9 21 23 6 23 16 11 22 20 8 23 18 9 21 22 7 20 19 11 18 23 9 18 22 10 17 23 10 21 19 10 17 25 8 23 20 7 18 23 9 22 16 12 21 19 10 20 19 11 22 17 11 20 21 9 26 14 10 22 18 10 22 20 8 20 21 9 16 26 8 19 20 11 22 20 8 19 20 11 19 22 9 20 21 9 20 20 10 20 19 11 22 16 12 24 17 9 20 19 11 22 20 8 19 22 9 21 20 9

answer:Since DNA is double-stranded, we know that the percentage of thymine in one strand should be equal to the percentage of adenine in the complementary strand, and the percentage of guanine in one strand should be equal to the percentage of cytosine in the complementary strand. We can use this information to predict the composition of the other bases in each sample: Sample A: Since the percentage of thymine is 17.9%, we know that the percentage of adenine should also be 17.9%. Let's call the percentage of guanine "G" and the percentage of cytosine "C". The total percentage of nucleotides in double-stranded DNA must add up to 100%. So we can write: 17.9% (T) + 17.9% (A) + G + C = 100% Simplifying: 35.8% + G + C = 100% G + C = 64.2% We also know that the percentage of guanine should be equal to the percentage of cytosine: G = C So we can write: G + G = 64.2% 2G = 64.2% G = C = 32.1% Therefore, the predicted base composition for Sample A is: 17.9% A 17.9% T 32.1% G 32.1% C Sample B: Using the same logic as above, we can write: 29.3% (T) + A + G + C = 100% A + G + C = 70.7% G = C 2G + A = 70.7% Substituting G=C: 3G = 70.7% G = C = 23.6% A = 70.7% - 2G = 23.6% Therefore, the predicted base composition for Sample B is: 23.6% A 29.3% T 23.6% G 23.6% C

answer:The temperature required to denature DNA depends on its base composition. Specifically, it depends on the proportion of G-C base pairs, which have three hydrogen bonds compared to the two hydrogen bonds in A-T base pairs. Therefore, the higher the G-C content, the higher the temperature required to denature the DNA. From the predicted base compositions calculated earlier, we can see that Sample A has a higher proportion of G-C base pairs (64.2%) compared to Sample B (47.2%). Therefore, Sample A is expected to have a higher temperature required to denature the DNA compared to Sample B.

answer:Yes, that's correct! Chargaff's rules dictate that in double-stranded DNA, the number of adenine nucleotides will be equal to the number of thymine nucleotides, and the number of guanine nucleotides will be equal to the number of cytosine nucleotides. This means that the percentage of adenine will be equal to the percentage of thymine, and the percentage of guanine will be equal to the percentage of cytosine. Additionally, the sum of the percentages of adenine and guanine will be equal to the sum of the percentages of thymine and cytosine, since the total number of A, T, G, and C nucleotides in double-stranded DNA must add up to 100%.