Answer
a) Yes, we can conclude that weather and mechanical failures caused 20% of recent plane crushes, for: $6+14=20$
b) $100-(40 + 5 + 6 + 14 + 6) =29$%.
c) Chart attached
Work Step by Step
The bar chart is a good choice as some categories have close values, which are not easily distinguishable in a pie chart.
