In an experiment with a stretched string, the distance between the first and the seventh crest in a photograph is measured as 1.20m±0.02m. At the same time, a stopwatch records that 50 complete oscillations occur in 2.0s±0.1s. Using these data, calculate the percentage uncertainty in the value of the wave speed obtained from the experiment.
a) Approximately 5.3%
b) Approximately 9%
c) Approximately 6.7%
d) Approximately 7.1%