Which vaccine company has developed Typbar Typhoid Conjugate vaccine that has received pre – qualification from the World Health Organisation (WHO)for global use ?
If D and E are points on the sides AB and AC respectively of a triangle ABC such that DE||BC. If AD = x cm, DB = (x – 3) cm, AE = (x + 3) cm and EC= (x – 2) cm, then what is the value (in cm) of x?