Answer:
7.7
Step-by-step explanation:
We have been given two measurements: 7 m and 7.7 m. We are asked to determine which measurement is more precise.
We know that precision is the level of detail of a measurement, determined by the smallest unit. It is fraction of a unit that can be  reasonably measured.
We can see that 7.7 is a detailed measurement, therefore, 7.7 is more precise.
