Answer:0.46
Explanation:
Given
Initial height 
inclination 
Thrust
combined mass of kieran and skis 
Speed at the bottom 
From Work Energy Theorem
Work done by all the force is equal to change in kinetic Energy
------------1
distance traveled along the slope 



substitute in 1




Depends on the elasticity and density of the medium through what it is traveling <span> </span>
Answer:
1 m = 100 cm....so 2.5 m = (2.5 * 100) = 250 cm
a = 1st shelf
b = 2nd
c = 3rd
d = 4th
a + b + c + d = 250
b = 2a + 18
c = a - 12
d = a + 4
a + (2a + 18) + (a - 12) + (a + 4) = 250
5a + 10 = 250
5a = 250 - 10
5a = 240
a = 240/5
a = 48 cm <== 1st shelf
b = 2a + 18 = 2(48) + 18 = 114 cm <== 2nd shelf
c = a - 12 = 48 - 12 = 36 cm <== 3rd shelf
d = a + 4 = 48 + 4 = 52 cm <== 4th shelf
so 2nd shelf is 114 cm
<span>10 hertz
Hertz is the frequency of oscillation which is the number of oscillations per second. So if something takes 0.10 s per oscillation, divide 1 second by the period to get the frequency. So
1 / 0.10s = 10 1/s = 10 Hertz
Therefore the object is vibrating at 10 hertz.</span>