A student wants to find the density of an irregular solid. She first hangs the solid from a spring balance and notes the reading. To obtain the mass from this reading before finding the volume, the student should divide the reading by g because the spring-balance reading represents
(a) the mass of the solid measured in newtons
(b) twice the weight of the solid measured in newtons
(c) the weight of the solid measured in newtons
(d) the weight of the solid measured in kilogramforce