Answer:

Step-by-step explanation:
Given
--- Amplitude
--- Right phase shift
Required
Identify the function
A sinusoidal function is defined as:

Substitute values for A and C

By comparison, only option (D) has the above format where

Hence (D) is correct
The first decimal point is tenth. 4.88
when rounding, we just look at the number right after the number you want to round to. it's 8 right? since 8 is closer to 10 than 0,
we round it to 4.9
(4.8 + 0.10)