a) curve: Helix
x= 3u*sin(5u); y= u*cos(3u); z= 5u; 0<= u <= 4 pi
b) 1- curve: sinus; x= 5sin*(3u); y= 3u; z= 1; 0<= u <= 2 pi;
2-curve: helix; x= 3v*sinus(5v); y= 1; z= 5v*cos(v); 0<=v<=4pi