4ms I'm just guessing by the way
Explanation:
It is given that,
Average power per unit mass generated by Lance, 

(a) Distance to cover race, 
Average speed of the person, v = 11 m/s
If t is the time taken to cover the race.


t = 14545.46 s
Let W is the work done. The relation between the work done and the power is given by :



W = 7090911.75 J
(b) Since, 
So, in 7090911.75 J, 
W = 1694.01 J
Hence, this is the required solution.
1)
HCl: hydrogen, chloride
3CO2: carbon, oxygen
2Na2SO4:sodium, sulphur, oxygen.
2)
-HCl: 1 hydrogen atom, 1 chlorine atom
-CO2: 1 carbon atom, 2 oxygen atoms
-Na2SO4: 2 sodium atoms, 1 sulphur atom, 4 oxygen atoms.
3)
-HCl: 2 atoms
-3CO2: 9 atoms
-2Na2SO4: 14 atoms.