21. Use the Disk/Washer or Shell method to set up the integral to find the volume of the solid obtained by rotation about y-axis the region bounded by y= squre root x+1 , x=0 and y=0?

22. How long does it take for 600 dollar to grow to 2400 dollar at an annual interest rate of 8 percent compounded continuously? Round the number of years to the nearest hundredth.

23. Which of the following is a hyperbola?

a. 9x^2 +9y^2-9=0

b. -7x^2+9y^2-9=0

c. 7x^2 +9y-9=0

24.Determine the area bounded by x=y^2+2 and x=3y?

25. The population of certain bateria has grown by 20 percent in 30 minites. Determine its growth rate constant, in a hour.?