Two parents both have brown eyes but are heterozygous at a locus that determines brown vs. blue eye color (the blue eye-color phenotype is recessive). If they have four children together, calculate the probability for each of the following scenarios. [For this problem, you should show simple calculations, but you do not need to answer in full sentences.] a. None of the children have blue eyes. b. At least one of the children has blue eyes. c. The first two children have blue eyes but the second two have brown eyes. d. Two of the children have blue eyes and two have brown eyes, regardless of order.