Data on sunspots shows that the number of sunspots varies across a regular solar cycle, repeating itself every 11 years. In 1750, there was recorded a maximum of 90 sunspots visible that year, with a minimum of only 10 sunspots visible several years earlier.

a) Determine the baseline, amplitude, and period of this solar cycle.

b) Let t represent the number of years after 1750 and let S(t) represent the number

of sunspots. Find a formula of the form S(t)=a cos⁡〖(bt)〗+d to model this scenario.

c) Using your model, estimate the number of sunspots in 1754 and 1743.