Significant Digits and Density?

I'm not sure how to round the answers to this question to have the correct number of significant digits.

Copper has a density of 8.92 g/mL. What mass of copper will occupy 45 mL? What volume of copper will have a mass of 1.0 kg (1000g)?

For the first part I got 401.4g, but there would only be two significant digits. So, would the answer be 400g since I can have no more than two significant digits?

For the second part I got around 112.1 mL, but again there would only be two significant digits. So, would the answer be 110mL since I can have no more than two significant digits? I’m just not sure about the rounding.

Thanks for your help!

Answer:
For the first part, since you're allowed 2 significant digits, write it as 4.0x10^2 to show that you have 2 sd, and not just the 1 that 400 implies.

Right on for the second part, 110 would be it.

P.S. I didn't check your math, just the rounding!
Multiplications / division you take the lowest number of sig figs for number you start the computation with. Both you volume and weight were to 2 sig figs, so your answer is 2 sig figs.

You did the rounding right, but there is one more thing… You need to place a line over the second “1” in 110 to illustrate than you’ve rounded this number to the tens place.

Samething on your 400, a line over the first "0".

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