
Multiply 4.8 into (20/3), and multiply 16/9 with (1.2b)

Multiply 9 on both sides
19.2b = 32(9)
19.2b = 288 Divide 19.2 on both sides
b = 15
Answer:
2π
Step-by-step explanation:
Period is the time it takes for the wave to reach one full cycle, which is the distance between the adjacent crests. The first crest is at 0 and the second crest is at 2π. Therefore, it takes 2π seconds to complete a full cycle. Hope this helps!