The answer would be:
B. Chlorine, iodine and Fluorine
Barium has 2 valence electrons. To satisfy the BaX₂ , this would mean that Barium will need to give one of each of its electrons. The elements that need 1 electron would be those that have 7 valence electrons to complete the octet. These elements would fall in group 7 or halogens. Chlorine, iodine and fluorine are all in Group 7, so this would be the best choice.
It would be D I believe! Depending on the angle of the mirror and distance positioned!
Answer:
a The kinetic energy is 
b The height of the center of mass above that position is
Explanation:
From the question we are told that
The length of the rod is 
The mass of the rod
The angular speed at the lowest point is 
Generally moment of inertia of the rod about an axis that passes through its one end is
Substituting values


Generally the kinetic energy rod is mathematically represented as



From the law of conservation of energy
The kinetic energy of the rod during motion = The potential energy of the rod at the highest point
Therefore



Answer:
25 seconds
Explanation:
Assuming the woman is accelerating at a constant rate of
from the initial velocity, u=4.20 m/s, to the final velocity, v=5.00 m/s.
Let she takes t seconds to cover the distance, s=115 m.
As acceleration, 

Now, from the equation of motion


[ from equation (i)]

seconds.
Hence, she takes 25 seconds to walk the distance.