A student performs two experiments to determine the coefficient of static and kinetic…

A student performs two experiments to determine the coefficient of static and kinetic friction between a block of mass 100 kg and the horizontal floor.
I^st Experiment: He applies a gradual increasing force on the block and is just able to slide the block when force is 450 N
II^nd Experiment: He applies constant force of different magnitudes for the duration of 2 s and determine the distance travelled by the block in this duration.
Set    Force Distance
1 .      300 N 0.5 m
2 .      600 N 2.0 m
3 .      750 N 3.0 m
Assume all the forces have been applied horizontally.
 
The coefficient of static friction between the block and the floor is