If a sound wave traveled from a solid to a liquid its speed would O Not enough information to determine the answer.
Speed up
O Stay the same speed
O Slow down

Slow Down, because sound waves travel faster through solids than through liquids.

A. This compound is Tin(IV) Sulfate, or Stannic Sulfate. It depends on which naming methodology you are using, but both are correct.

B. The molar mass of this compound is calculated by the combination of the formula weights of all the pieces of the compound, so you need to add the weights of

Sn+2S+8O
118.7 + 2(32.07) + 8(15.99)
118.7 + 64.14 + 127.92
310.76

The molar mass is 310.76 g/mol.