Final answer:
The number 0.00456 in scientific notation with correct significant figures is 4.56×10⁻³, corresponding to answer choice (a).
Step-by-step explanation:
The student has asked how to express the number 0.00456 in scientific notation with correct significant figures. To convert a number into scientific notation, you must move the decimal point to the right of the first non-zero digit and then count the number of places the decimal point has moved. In this case, the decimal point moves three places to the right, making the exponent for 10, -3. Therefore, the correct scientific notation for 0.00456 with the correct significant figures is 4.56×10⁻³. This corresponds to answer choice (a).
To express the number 0.00456 in scientific notation with correct significant figures, we consider the significant figures in the original number, which are 3. The scientific notation should have the same number of significant figures. So, 0.00456 can be written as 4.56 x 10-3. Option a) 4.56 x 10-3 is the correct expression.