Looking for the sum and the difference for each B.) and C.)
For Tran.

Step-by-step explanation:
b) sum: (614 m + 304 m) +- 1.0 m
= 918 m +- 1.0 m
difference = (614 m - 304 m) +- 1.0 m
= 310 m +- 1.0 m
c) sum = (1400 kg + 900 kg) +- 100 kg
= 2300 kg +- 100 kg
difference = (1400 kg - 900 kg) +- 100 kg
= 500 kg +- 100 kg