Answer:
The amplitude is 3 and the period is 10π/9.
Explanation:
The standard cosine function is in the form:

Where |a| is the amplitude, 2π/b is the period, c is the phase shift, and d is the vertical shift.
We have the function:

We can rewrite this as:

Therefore, a = 3, b = 9/5, c = 0, and d = 0.
Hence, our amplitude is |3| = 3.
Our period will be:
