360 / 15 = 24 spokes
360 / 30 = 12 , so 12 spokes in that wheel.
This completely depends on the wheel. The most common number of spokes per wheel is 36. Some better wheels have 32. Higher performance wheels have even less.
180
It will form a 300 degrees reflex angle
There is 1 angle between each pair of rays. So 30 rays equals 30 angles. But, if the angles are likened to the spokes of a bicycle wheel, should the 30 rays not completely fill the circumference of the wheel, the 2 outer rays also form an angle. So the possible total is 31 angles.
360 / 30 = 12 , so 12 spokes in that wheel.
This completely depends on the wheel. The most common number of spokes per wheel is 36. Some better wheels have 32. Higher performance wheels have even less.
That would differ from one bike to another. A really small bike with maybe 12" wheels will have fewer spokes than a bike with 20" wheels. Say between 24 and 36.
24 spokes
A wheel with 64 spokes will have 64 spaces between the spokes.
There are many types of spokes. Some are the spokes on a bicycle, another are the spokes on a wheelchair, or you can even find them on baby carriages.
A wheel with 10 spokes will have 10 spaces between the spokes.
There are 24 spokes
The stock Explorer rims have 5 spokes
The spindle and hub is connected to the rim by 64 spokes
Assuming all the spokes have the same mass and density distribution, I do not think there is any reason a 7 spoke wheel should be inherently inbalanced, as long as the angle between adjacent spokes is equal to 360/7 degrees. Similarly, a 3 spoke wheel would be balanced if the angle between adjacent spokes was 120 degrees. If you draw a line from one side of the wheel to the other that passes through the centre of the wheel and then calculate all the compenent forces parallel to that line, you will see they all balance out. Look up adding vectors and finding the component of a force if you want to do the maths. The doubt makes sense because 360/7 results in a fractional value unlike say 360/3 but one must remember that it is possible to analyze this fraction up to the required degree of accuracy. Also wheels anyway have to be balanced by adding weights after the manufacturing so as to correct errors in the manufacturing process so the same can be applied over here.
A wheel with 12 spaces will have 12 spokes.