Keiko is mixing 4 cups of concrete to make a stepping stone. she needs 1.5 cups of sand and 2.5 cups of cement mix. which statement best describes how much of each ingredient keiko needs to measure? a. keiko should make it easy and just measure about 1 cup of sand and 3 cups of cement mix since she needs a total of 4 cups. b. keiko should measure exactly 1.5 cups of sand and 2.5 cups of cement mix to be sure the concrete will set properly. c. keiko should make it easy and just measure about 2 cups of each since she needs a total of 4 cups.