Read the passage Mosby Science Museum: Volunteer Opportuniti…

Read the passage Mosby Science Museum: Volunteer Opportunities, and then answer the following question(s).The museum needs two volunteer ushers for each shift. A new employee in the Volunteer Services office has scheduled five 8th- and 9th-grade ushers for the last weekend in April. The schedule appears below. Hours Sat Sun 10 A.M. to 1:30 P.M. Caleb & Bettina   1:30 P.M. to 5 P.M. Rachel & Esteban   11 A.M. to 2:30 P.M.   Sunita & Rachel 2:30 P.M. to 6 P.M.   Rachel & Esteban What is wrong with the schedule?