Answer:

Explanation:
Since, Alex is at rest. Therefore, the speed measured by him will be the absolute speed of car P. Therefore, taking easterly direction as positive:
And the absolute velocity of Barbara's Car is given as:
Now, for the velocity of Car p with respect to the velocity of Barbara's Car can be given s follows:


Balance tubes by spacing them equally around the centrifuge and Always balance tubes with other tubes containing a same volume of liquid are right.
If you don't space them out equally, you will have a lot of broken glass to clean up...trust me. The same thing can happen if you don't have equal amounts of liquid in each tube, but it doesn't have to be exactly the same in every one.
Explanation:
It is given that, the range of human hearing is roughly from twenty hertz to twenty kilohertz.
Minimum frequency, f = 20 Hz
Maximum frequency, f' = 20,000 Hz
We need to find the lengths of the longest and shortest pipes. For open pipes, the length of pipe is given by :

For shortest pipe, frequency should be maximum, 
l = 0.008575 m
For longest pipe, frequency should be minimum, 
l' = 8.575 m
So, the lengths of longest and shortest pipes are 8.575 meters and 0.008575 meters respectively.
An antibaryon composed of two antiup quarks
and one antidown quark would have a charge of (2) −1e.