Why do economics often use the other things constant assumption when they develop econonmic theories?

Case in point 1.2 suppose you work in the it department of global hotels, a multinational hotel chain. global hotels runs several specialized business support systems, including a guest reservations system that was developed in-house to meet the requirements of a large company with worldwide operations. guests can make one-stop online reservations by visiting global's website, which has links to all major travel industry sites. global hotels just acquired momma's, a regional chain of 20 motels in western canada. momma's uses a vertical reservations package suitable for small- to medium-sized businesses and a generic accounting and finance package. should momma's use global hotels' information systems or continue with its own? in your answer, consider issues such as business profiles, business processes, system interactivity, edi, ecommerce, and the characteristics of both information systems. what additional information would be to you in making a recommendation?

Rachel died in 2014 and her executor is finalizing her estate tax return. the executor has determined that rachel’s adjusted gross estate is $10,120,000 and that her estate is entitled to a charitable deduction in the amount of $500,000. using 2014 rates, calculate the estate tax liability for rachel’s estate.

Job 456 was recently completed. the following data have been recorded on its job cost sheet: direct materials $ 2,418 direct labor-hours 74 labor-hours direct labor wage rate $ 13 per labor-hour machine-hours 137 machine-hours the corporation applies manufacturing overhead on the basis of machine-hours. the predetermined overhead rate is $14 per machine-hour. the total cost that would be recorded on the job cost sheet for job 456 would be: multiple choice $3,380 $5,298 $6,138 $2,622