solving problems by relating sinusoidal wave and vector functions to their respective engineering applications

Full and clear Answers needed for LO3 part a) 1,2,3,4. , you need to answer all sub-questions of part a (LO3 part a). please refer to the scenario that is given on the first page and read the question clearly. Replay me only who can do the all of 4 sub-questions. The answers need to submit today itself.

Use analytical and computational methods for solving problems by relating sinusoidal wave and vector functions to their respective engineering applications.

a) A system of solar panels produces a daily average power P that changes during the year. It
is maximum on the 21st of June (day with the highest number of daylight) and equal to 20
kwh/day. We assume that P varies with the time t according to the sinusoidal function P(t)
= a cos [b(t - d)] + c , where t = 0 corresponds to the first of January, P is the power in
kwh/day and P(t) has a period of 365 days (28 days in February). The minimum value of P
is 4 kwh/day.
1- Find the parameters a, b, c and d.
2- Sketch P(t) over one period from t = 0 to t = 365.
3- When is the power produced by the solar system minimum?
4- The power produced by this solar system is sufficient to power a group of machines if the
power produced by the system is greater than or equal to 16 kwh/day. For how many days,
in a year, is the power produced by the system sufficient?