$\begin{array}{1 1}\text{a. The mass of a substance is a way to measure the amount of matter it contains.} \\ \text{
b. Mass is a way to measure the force of gravity on a substance.} \\ \text{
c. The mass of a substance may change, based on its location.} \\ \text{
d. Mass is a chemical property of a substance. }
\end{array} $