1. The problem asks to identify the correct definition of significant figures. Answer C is correct: "The first non-zero digit and all the digits that follow" because significant figures include all digits starting from the first non-zero digit. 2. Counting the number of significant figures in 0.00564. There are three significant figures (5, 6, 4) because leading zeros are not significant. Answer: B (3) 3. Identifying the least significant figure in the number 7.502. Digits: 7 (most significant), 5, 0, 2 (least significant digit is the rightmost digit). Answer: D (2) 4. Find the number with 4 significant figures. A. 0.0120 has 3 significant figures (1, 2, and trailing zero). B. 1200 is ambiguous without a decimal; often 2 significant figures. C. 0.00012 has 2 significant figures. D. 120.0 has 4 significant figures because trailing zero after decimal is significant. Answer: D (120.0) 5. Convert $3.25 \times 10^{4}$ to standard form: $3.25 \times 10^{4} = 32500$ Answer: C (32500) 6. Number of significant figures in 700040. Assuming no decimal shown, trailing zeros before non-zero digit count. Digits: 7, 0, 0, 0, 4, 0 Here, zero between 7 and 4 are significant, trailing zero after 4 is significant. Count: 6 Answer: D (6) 7. Standard form of $5.6 \times 10^{-3}$: Move decimal 3 places left: $0.0056$ Answer: B (0.0056) 8. Addition $7.452 + 3.18$ rounded to three significant figures. Sum: $7.452 + 3.18 = 10.632$ Rounding to 3 significant figures: $10.6$ Answer: A (10.6) 9. Convert $9.75 \times 10^{-2}$ to standard form: Move decimal 2 places left: $0.0975$ Answer: A (0.0975) 10. Product of $2.3 \times 10^{3}$ and $1.5 \times 10^{-2}$: Multiply numbers: $2.3 \times 1.5 = 3.45$ Add exponents: $3 + (-2) = 1$ So product: $3.45 \times 10^{1} = 34.5$ Answer in scientific notation: $3.45 \times 10^{1}$ (not listed), closest answer is B (34.5 x 10-3) which is incorrect. Re-examining options, actual product is $3.45 \times 10^{1}$, none match perfectly. So the correct scientific notation is $3.45 \times 10^{1}$, but answer closest by magnitude is B if considering format error. Final answers: 1: C 2: B 3: D 4: D 5: C 6: D 7: B 8: A 9: A 10: None perfectly match; correct product is $3.45 \times 10^{1}$.