Answer:
A
Step-by-step explanation:
My brain is big now trust me ;)
This is a tricky question that Reina and Sam are multiplying (84)5 (73)9and their work are (84)5 (73)9 = 84 + 573 + 9 = 89712 Reina's(84)5 (73)9 = 84⋅573⋅9 = 820727 Sam'sActually they are doing or multiplying using exponents.
Reina’s work (8⁴)₅(7³)⁹=8⁴⁺⁵+ 7³⁺⁹= 8⁹ 7¹²This is incorrect because she added exponents instead of multiplying exponents
Sams work (8⁴)⁵ (7³)⁹=8⁴ˣ⁵ 7³ˣ⁹= 8²⁰ 7²⁷This is correct because Sam multiplied exponents correctly
Exponents are multiplied not added.
Think: Coffee is entering the urn at the same time that coffee is being withdrawn from the urn. Generally the former rate is greater than the latter, 'tho this is not always the case. (e - l)(t) signifies the NET amount of coffee in the urn. If e - l is decreasing, then the amount of coffee there is decreasing. If e - l is increasing, then the amount of coffee in the urn is increasing, and the urn could eventually overflow. Please use this info to select the correct answer.