If one parrent is O plus and the other b- what will child be?

The possible blood types of the child are A positive, A negative, B positive, or B negative.

The O positive parent can only pass on O alleles, while the B- parent can pass on either B or O alleles. Therefore, the possible genotypes of the child are OO, AO, BO, or AB.

The O positive parent can only pass on the Rh positive allele, while the B negative parent can pass on either the Rh positive or Rh negative allele. Therefore, the possible Rh phenotypes of the child are positive or negative.