A particle `P` starts from the point `z_0=1+2i ,` where `i=sqrt(-1)` . It moves first horizontally away from origin by 5 units and then vertically away from origin by 3 units to reach a point `z_1dot` From `z_1` the particle moves `sqrt(2)` units in the direction of the vector ` hat i+ hat j` and then it moves through an angle `pi/2` in anticlockwise direction on a circle with centre at origin, to reach a point `z_2dot` The point `z_2` is given by (a)`6+7i` (b) `-7+6i` (c)`7+6i` (d) `-6+7i`