The conversion factor between radians and revolution as measures of angle is 2π rad is equal to 1 revolution. Converting the given angular velocity to rev/s,
(2.8 rad) x (1 rev / 6.28 rad) = 70/157 revolution per second
Dividing the given angle, 20 rev by the velocity,
(20 rev) / (70/157 rev/s) = 44 6/7 s
Thus, the answer is approximately 44.9 seconds.
It is centered at (h,k) --> (0,0) and has a radius 9
The equation of the circle is

Hope that helps!
Answer:

that is the required inequality
You might have made an error the first time you solved for x. I got x = -0.5.
When you have your log base 4, the way you cancel that out is by making 4 the base on both sides, so you get 4^(log4) to reduce to 1, and you're left with:
2x + 3 = 4^(1/2) ... Simplify
2x + 3 = 2
2x = -1
x = -1/2
If you plug that back in, everything checks out. Maybe double check your use of logarithm/exponent properties?