A biologist measured the lengths of hundreds of cuckoo bird eggs. Use the relative frequency distribution below to answer the questions that follow, Lengths of Cuckoo Bird Eggs Length (in millimeters) Percent of eggs 18.75-19.75 0.8 19.75 -20.75 4.0 20.75-21.75 17.3 21.75-22.75 37.9 22.75-23.75 28.5 23.75-24.75 10.7 24.75-25.75 0.8 (a) What percent of the group of eggs was less than 21.75 mm long? (b) What is the probability that one of the eggs selected at random was at least 21.75 mm long but less than 23.75 mm long