Grace and Jamal each bought notebooks for school. Grace bought 2 notebooks for $2.80 while Jamal bought 4 notebooks for $4.40. What was the unit price of each student's notebooks?

A. Grace: $1.40; Jamal: $1.10

B. Grace: $2.80; Jamal: $4.40

C. Grace: $1.10; Jamal: $1.40

D. Grace: $2.00; Jamal: $4.00