Not sure this is a physics question (probably biology).
Anyway, the correct answer is A):
"Plasticity helps us to adapt to our environment. It also generally decreases with age".
Plasticity is the ability to adapt to the environment. Since this ability is linked with brain functions, and brain functions worsen with age, then plasticity decreases with age.
Answer:
Hans Christian Oersted began a new scientific epoch when he discovered that electricity and magnetism are linked. He showed by experiment that an electric current flowing through a wire could move a nearby magnet. The discovery of electromagnetism set the stage for the eventual development of our modern technology-based world.
Explanation:
Displacement is d
Vf² = Vi² + 2 g d
(-20²) = (+10²) + 2 (-9.8) d
-19.6 d = 300
d = -15.3 m
negative means lower
time is t
d = Vi t + 1/2 g t²
-15.3 = 10 t + (-4.9) t²
4.9 t² - 10 t -15.3 = 0
t = 3.06 s
Hope this helps -John
A) 
The energy of an x-ray photon used for single dental x-rays is

The energy of a photon is related to its wavelength by the equation

where
is the Planck constant
is the speed of light
is the wavelength
Re-arranging the equation for the wavelength, we find

B) 
The energy of an x-ray photon used in microtomography is 2.5 times greater than the energy of the photon used in part A), so its energy is

And so, by using the same formula we used in part A), we can calculate the corresponding wavelength:

Answer:
The time taken will be 0.553 seconds.
Explanation:
We should start off by finding the force exerted by the rope on the 3kg weight in this case.
Weight of 5kg mass = 5 * 9.81 = 49.05 N
Weight of 3kg mass = 3 * 9.81 = 29.43 N
The force acting upward on the 3kg mass will equal the weight of the 5kg mass. Thus the resultant force acting on the 3kg mass is:
Total force = 49.05 - 29.43 = 19.62 N (upwards)
We can now find the acceleration:
F = m * a
19.62 = 3 * a
a = 6.54 m/s^2
We now use the following equation of motion to get the time taken to travel 1 meter:


t = 0.553 seconds