Answer:
The ratio of the orbital time periods of A and B is 
Solution:
As per the question:
The orbit of the two satellites is circular
Also,
Orbital speed of A is 2 times the orbital speed of B
(1)
Now, we know that the orbital speed of a satellite for circular orbits is given by:

where
R = Radius of the orbit
Now,
For satellite A:

Using eqn (1):
(2)
For satellite B:
(3)
Now, comparing eqn (2) and eqn (3):

Answer:
The potential energy of the rock = 10.5 kN
Explanation:
Mass of rock = 25 kg
Acceleration due to gravity = 10 m/s²
Height = 42 m
Potential energy, PE = mgh, where m is the mass, g is acceleration due to gravity and h is the height.
PE = 25 x 10 x 42 = 10500 N = 10.5 kN
The potential energy of the rock = 10.5 kN
The ratio of concentration of ionized acid to the initial concentration of acid multiplied by 100 will give the percent ionization of a weak acid in water increases as the concentration of acid decreases.
Explanation:
Percent ionization is used for quantifying the number of ions present in the weak acid when dissolved in a solution. So it is similar to the pKa value. The percent ionization value can be determined as negative log of dissociation constant. Also the as the number of ions increases in weak acid, the concentration of acid will be decreasing . It can be calculated using the formula for percent ionization as follows:

As the water volume or concentration increases, the acid will get diluted much more thus leading to decrease in the concentration of acid.
So the ratio of concentration of ionized acid to the initial concentration of acid multiplied by 100 will give the percent ionization of a weak acid in water increases as the concentration of acid decreases.
Answer:
D
Explanation:
they can see this along with many other fish.
It is based on atomic number, which is the number of protons in the nuclei of the atoms of an element.