Answer:
a) 
b) 
Explanation:
Given:
height of water in one arm of the u-tube, 
a)
Gauge pressure at the water-mercury interface,:
we've the density of the water 
b)
Now the same pressure is balanced by the mercury column in the other arm of the tube:
<u>Now the difference in the column is :</u>
Answer: velocity = -0.65 speed =0.65
Explanation:
Velocity =speed+direction speed =distance/time
First we find the energy level with the following formula, where a is the energy level, n1 is the final energy level, n2 is the starting energy level and r is Rydberg's constant in Joules
We insert the values
The wavelength is found with this formula, where h is Planck's constant and c is the speed of light
Finally we insert the values
Which is the same as 93.8 nm
Gravitational force depends on inverse square law. That is, gravitational force is inversely proportional to square of distance between asteroids.
As distance between them decreases, gravitational force increases. Hence A is correct.
