We have

so this is indeed a difference of squares. Factorizing would give

making the answer D.
We can further factor the first term here and write

but that's clearly out of the scope of this question.
Answer:
<em>SOLUTION: Over the last three evenings, Heather received a total of 109 phone calls at the call center. The third evening, she received 4 times as many calls as the second evening</em>
You can use the sum and difference identities which for cosine is cos(a+b)= cosacosb-sinasinb
Answer:
684
Step-by-step explanation:
57 times 12
12 weeks times 57 pages= 684 pages in 12 weeks
Answer:
2km
Step-by-step explanation: