Answer:
8.73
Step-by-step explanation:
when you are adding or subtracting numbers, the sigfig (significant figure) is based on how many numbers after the decimal. with this info, we can see that 15.67 has 2 sigfigs and 6.943 has 3 sigfigs. when you subtract normally, you would get 8.727, which has 3 sigfigs, so you would round the last 7 up to get 8.73 with 2 sigfigs!
also it is to 2 sigfigs because we know that we go by the least number of sigfigs. hope this helped!