I like playing basketball. So I'm the object in motion. Until an unbalanced force comes and hits me I fall and stay at rest.
Answer:
a). Maximum Length L=0.929m
b). T=0.83 Hz or 1.2s
c). Longer, the effortless waling T=2.1 Hz or t=0.475s
d). t=1.2s V=0.774 
t=0.475s V=1.95 
Explanation:
Length legs=L=1.1m
angle=50
the step that give the person forms a triangle whose two sides are known and the angle that forms between them, then using trigonometry as the image
Divide the original triangle in two and form a right triangle so the angle is 25 and the L is hypotenuse and the opposite is the step length
a).


Length of the step
L=0.464m*2
L=0.928m
b).
period=T

c).

The period is the inverse of the time of the motion so, the T1 is faster that the T because

d).
The speed is the relation between the distance with time so:

The answer of this question is called uplift i.e the rising of rock layers in geology is called uplift.
Uplift is the process in which there will be vertical elevation of earth surface due to various natural processes occurring inside the surface of earth like earth quakes. Sometimes uplift is also caused by the mountain building which hampers the balance of a particular region.
In the process of uplift,the rocks normally metamorphic rocks present underground will be brought up to the earth surface.The enhanced elevation will cause erosion of lot of materials on the surface of earth.