Answer:
They are the only joints that can do 360 degrees and rotate with their own axis. But, because of its free-moving, it is prone to any dislocation compared to other movable joints.
Explanation:
Answer:

Explanation:
We know that there is a relation between the speed of light ,frequency and wavelength.This relation can be given as
where v is speed of light
is frequency of light
is wavelength of light
In first case we have given λ=655 nm
so using formula 

Hz
In second case we have wavelength 515 nm so by using above formula


In third case we have wavelength 475 nm
so 

Explanation:
hi do u mind helping me with something lmak
Answer:
21 seconds
Explanation:
First, convert km/hr to m/s.
69 km/hr × (1000 m / km) × (1 hr / 3600 s) = 19.2 m/s
Distance = rate × time
400 m = 19.2 m/s × t
t = 20.9 s
Rounded to two significant figures, it takes the horse 21 seconds.