Final answer:
Sao saves $550.20 in a year with the new service compared to the old service.
Step-by-step explanation:
To find out how much Sao will save in a year with the new service compared to the old service, we need to calculate the difference in the monthly charges. The difference is $145.84 - $99.99 = $45.85. So Sao will save $45.85 per month with the new service. To calculate the annual savings, we multiply the monthly savings by 12, since there are 12 months in a year. Therefore, Sao will save $45.85 * 12 = $550.20 in a year with the new service compared to the old service.