3. [12 Points] 2004 What does / fKt) dt represent if {(t) is the rate at which the world's population is growing in year t and is given in billions of people per year? 2000 This integral represents between the years of 2000 and 2004. The units of this Integral are . 4. [12 Points] 9 What does / a(t) dt, represent if a(t) is acceleration in km/hr2 and tis time in hours? 0 This integral represents Select v between t : 0 and L' : 9. The units of this integral are -Select- v . 5. [-12 Points] 5 What does / s(x) dx represent if s(x) is the rate of change of salinity (salt concentration) in gm/Iiter per cm in sea water and X is the depth below the surface of the water in cm? 0 This integral represents between the surface of the water and a depth of 5 cm. The units of this integral are