D, 0.140 liters! Hang on a sec and I'll show you a trick I use.
Answer:
a)
, b)
, c) 
Explanation:
a) The change in the gravitational potential energy of the marble-Earth system is:


b) The change in the elastic potential energy of the spring is equal to the change in the gravitational potential energy, then:

c) The spring constant of the gun is:




If it starts from 0m/s...
s=?
u=0
a=-10
t=8
s=ut +1/2at^2
so s=(0×8)+ (0.5×-10×64)
s=0+(32×-10)
s=32×-10
s=-320metres
The answer that completes the statement is this: A PHOTOGRAPH OF THE PARTICIPANT'S FIRST-GRADE CLASS INCREASED THE LIKELIHOOD OF FALSE MEMORIES. This experiment is similar to Maryanne Gary's experiment which also states that viewing memory as a tape or video recording can be mistaken and may create false memories.
It is <span>C. Low to moderate level of exertion can be sustained over long periods of time </span>