A scientist obtains the number 0.045006700 on a calculator. If this number actually has four significant figures, how should it be written?

Correct Answer: C

Rationale: The correct answer is C: 0.045. When dealing with significant figures, trailing zeros after the decimal point are considered significant. In this case, the number 0.045006700 should be rounded to 0.045 since it has four significant figures. Choice A has too many significant figures, B rounds incorrectly, and D removes significant figures after the decimal point. Thus, C is the correct choice.

Correct Answer: D

Rationale: The correct answer is D because when alpha particles are beamed at a thin metal foil, some pass directly through due to their small size and high energy (option A), while others are reflected by direct contact with nuclei in the metal foil (option C). This is based on the Rutherford scattering experiment which showed that alpha particles can be deflected by the positive nuclei in the metal foil. Option B is incorrect as alpha particles are not diverted by attraction to electrons in the foil. Option D combines the correct explanations for the behavior of alpha particles when beamed at thin metal foil.

Correct Answer: B

Rationale: To convert 4338 mL to qt, first convert mL to L by dividing by 1000 (4338 mL / 1000 = 4.338 L). Then, convert L to qt using the conversion factor 1 L = 0.946 qt. So, 4.338 L * 0.946 qt/L = 4.092 qt (Answer B). Choice A (4598 qt) is incorrect as it does not follow the correct conversion process. Choice C (4.092 10 3 qt) is incorrect due to incorrect formatting and notation. Choice D (4092 qt) is incorrect as it uses the wrong conversion factor.

Correct Answer: C

Rationale: The correct answer is C: 0.045. When dealing with significant figures, trailing zeros after the decimal point are considered significant. In this case, the number 0.045006700 should be rounded to 0.045 since it has four significant figures. Choice A has too many significant figures, B rounds incorrectly, and D removes significant figures after the decimal point. Thus, C is the correct choice.

Correct Answer: A

Rationale: To calculate the grams of manganese in a 206 lb body, first convert pounds to kg (206 lb = 93.44 kg). Then, use the given percentage (3 10–4%) to find the amount of manganese in the body (93.44 kg * 0.0003 = 0.028032 g). Since 205 lb = 1 kg, the correct answer is 0.028032 g or approximately 0.59 g (rounding). Summary of other choices: B: Incorrect, this does not consider the correct conversion and percentage calculation. C: Incorrect, this is a much larger value and does not align with the given percentage. D: Incorrect, this is also a much larger value and does not align with the given percentage.