Your Company Is Evaluating Two Cloud-Based Secured Data Storage Services $\sigma$

Your company is evaluating two cloud-based secured data storage services."Pie in the Sky," the newer service,claims its uploading and downloading speeds are faster than the older service,"Cloudy but Steady Skies." You need to make a decision based on published access times for both services at different times and for varying file sizes.To make your decision,you purchase a statistical study,which indicates that average download time for Pie in the Sky is 0.77 sec.per MB and for Cloudy but Steady Skies is 0.84.Assume that n₁ = n₂ = 50, $\sigma$ ₁ = 0.2 and $\sigma$ ₂ = 0.3.With $\alpha$ = .05,the observed z value is ______.

A) −9.71
B) −1.37
C) −0.7
D) 1.37
E) 1.96