Please help!! I just can't figure these questions out... and yes I have taken notes, I just can't figure these answers out. !

7. y = 1/4 • cos ( -θ/3 + 90 )
8. y = 4sin θ/4 + 1
9. y = 3cos θ/3
10. y = cos ( θ/3 - 45 ) + 2

find the Amplitude, Period, Minimum, Maximum, Midline, Domain, and Range for each of these^

I seriously appreciate you for helping out!! <3
I may or may not have already failed these questions twice...

Use the frequency distribution, which shows the number of american voters (in millions) according to age, to find the probability that a voter chosen at random is in the 18 to 20 years old age range. ages frequency 18 to 20 5.9 21 to 24 7.7 25 to 34 20.4 35 to 44 25.1 45 to 64 54.4 65 and over 27.7 the probability that a voter chosen at random is in the 18 to 20 years old age range is nothing. (round to three decimal places as needed.)