Answer:
Consider the alleles of the red cow to be CR, CR. Consider the genes of the roan cow to be CR and CW.
CR CW
CR CRCR CRCW
CR CRCR CRCW
The results of the punnet square show that there is a 50% chance that the offsprings will be red cow. The chances for Roan cow will also be 50%. The chances for white cow will be 0%.
Such kind of phenomenon is termed as co- dominance. In this case, the dominant allele is not fully dominant over the recessive allele.