Please answer both questions i will fail if i don't get these

Which of these people has balanced their checkbook correctly? oa. gary: the balance in his check register is $500 and the balance in his bank statement is $500. b. gail: the balance in her check register is $400 and the balance in her bank statement is $500. c. gavin: the balance in his check register is $500 and the balance in his bank statement is $510.

Tcan be concluded that % of the seniors would prefer to see more candid pictures in this year's edition of the yearbook.

Determine the difference: 3.2 × 1010 – 1.1 × 1010. write your answer in scientific notation.