Help needed on trig transformations
This table of values states the average monthly temperature

JAN, FEB,MAR,APR,MAY,JUN,JUL,AUG,SEP,OCT,NOV,DEC
16.5,18.3,21.8,25.5,29.2, 31.9,32.6,32.4,30.3,26.4,21.3,18.0

1. What characteristics of the function correspond to the constants a, b, c, and d?

2. Determine the temperature function T(t). [Hint: Consider January to be Month 0, February to be Month 1, etc.]

T(t)asin[b(t-c]]+d

I was thinking "a" is 8.05 and "d" was 24.55.

Question

Help needed on trig transformations
This table of values states the average monthly temperature  

JAN, FEB,MAR,APR,MAY,JUN,JUL,AUG,SEP,OCT,NOV,DEC
16.5,18.3,21.8,25.5,29.2, 31.9,32.6,32.4,30.3,26.4,21.3,18.0

1. What characteristics of the function correspond to the constants a, b, c, and d?

2. Determine the temperature function T(t). [Hint: Consider January to be Month 0, February to be Month 1, etc.]

T(t)asin[b(t-c]]+d

I was thinking "a" is 8.05 and "d" was 24.55.