It is a polynomial equation in y′ and the highest power raised to dy
dx
is one, so its degree is one (ii)
The highest order derivative present in the given differential equation is 
2
d y2
dx
, so
its order is two It is a polynomial equation in 
2
d y2
dx
 and dy
dx  and the highest
power raised to 
2
d y2
dx
 is one, so its degree is one (iii)
The highest order derivative present in the differential equation is y′′′, so its
order is three