Two scales are shown in Figure, a balance (a) and a spring scale (b). In the balance, cali...

Two scales are shown in Figure, a balance (a) and a spring scale (b). In the balance, calibrated weights are placed in one pan to balance the object to be weighed in the other pan. In the spring scale, the object to be weighed is placed on the pan and a spring is compressed that moves a dial on a scale in kilograms.

State for each device whether it directly measures mass or weight. Underline your answer. State in one sentence for each the reason for your answer.

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