A wooden object has a mass of 10.782 g and occupies a volume of ...

[BrownTown3]

A wooden object has a mass of 10.782 g and occupies a volume of 13.72 mL. What is the density of the object determined to an appropriate number of significant figures?
 
  A) 8  10-1 g/mL
  B) 7.9  10-1 g/mL
  C) 7.86  10-1 g/mL
  D) 7.859  10-1 g/mL
  E) 7.8586  10-1 g/mL

Question 2

Calculate the percentage by mass of oxygen in Pb(NO3 )2.
 
  A) 9.7
  B) 14.5
  C) 19.3
  D) 29.0
  E) 33.4

[bob]

Answer to Question 1

D

Answer to Question 2

D