Answer:
156.67 m/s
0.45676 times the speed of sound
Explanation:
Distance from the ground = 23.5 km = 23500 m
Time taken by the blast waves to reach the ground = 
Spedd of the wave would be

The velocity of the blast wave is 156.67 m/s
v = Velocity of sound = 343 m/s

The blast wave is 0.45676 times the speed of sound
a renewable energy source from living or recently living plant and animal materials which can be used as fuel. An example of biomass is plant material that produces electricity with steam. An example of biomass is animal fossil fuel.
A gerund usually ends wit -ing, so we must find the word that includes that.
Loading includes ing at the end.
Final answer: b. loading