Each day Sue works $8$ hours and produces $7$ units of goods and services. Mary works $10$ hours each day and produces $10$ units of goods and services. It follows that

a$.$ Sue's income per hour will be higher than Mary's.

b$.$ Sue's productivity is higher than Mary's.

c$.$ Mary's productivity is higher than Sue's.

d$.$ Sue's income per day will be higher than Mary's.