The annual revenue of Amazon over the period 2006-2010 can be approximated by a ( t ) = 2 e 0.25 t b i l l i o n d o l l a r s p e r y e a r ( 6 ≤ t ≤ 10 ), where t is the time in years since the start of 2000. Find an expression for the total annual revenue A ( t ) earned since the start of 2006, and use it to estimate the total revenue earned from the start to 2006 to the start of 2009. Round answer to the nearest $ billion. Do not include a dollar sign with your answer below. Hints: A ′ ( t ) = a ( t ) and A ( 6 ) = 0. Why?

Which of the following statements is not correct? 1) trade allows for specialization. 2) trade has the potential to benefit all nations. 3) trade allows nations to consume outside of their production possibilities curves. 4) absolute advantage is the driving force of specialization.

In a high school with 3000 students, counselors are putting together a math tutoring program for the neighboring middle school. they plan to invite high school students with high average test scores to tutor middle school students, and they would like to offer gift cards to the student tutors. the counselors have a spreadsheet showing each student’s average test scores, and in order to find out how many gift cards they should purchase, the counselors need to count how many students would qualify to become tutors. which type of function would best the counselors determine the number of eligible students?

2. how has taobao created economic opportunities for chinese entrepreneurs that were inaccessible to them before?