If the lead can be extracted with 92.5% efficiency, what mass of ore is required to make a lead sphere with a 4.00 cm radius?

What is the result of multiplying (2.5 × 1010) × (2.0 × 10-7)? a. 5.0 × 103 b. 5.0 × 10-3 c. 5.0 × 1017 d. 5.0 × 10-17

Which of the following is not a true statement about dwarf planets? a the kuiper belt contains comets, asteroids, and dwarf planets. b ceres is a dwarf planet located in the kuiper belt. c the largest known dwarf planet in the solar system is named eris.

Match the vocabulary terms to their definitions. 1 . a long, chain-like set of molecules made up of repeating units joined end to end polymer 2 . a hard, brittle, heat- and corrosion-resistant material made by subjecting a nonmetallic mineral mixture to intense heat ceramic 3 . a plastic with low elongations that cannot be recycled thermoset 4 . a carbon fiber embedded in a polymer resin matrix thermoplastic 5 . a plastic with high elongations that can be recycled crystal 6 . a solid form resulting from the arrangement of atoms, ions, or molecules in definite geometric patterns composite