Answer:
76,800
Step-by-step explanation:
Given the following :
Length = 20 kilometers
Width = 12 kilometers
Population density = 320 people per sq km
Population =?
Recall:
Area of rectangle = Length × width
Therefore,
Area of Rectangleville = 20 km × 12 km = 240km^2
Population is related to population density and Area by the formula ;
Population density = population ÷ Area
Therefore,
Population = population density × Area
Population = 320 × 240 = 76,800
Therefore, the population of Rectangleville is 76,800 people
Answer:
After 14.92 seconds, the arrow hits the ground.
Step-by-step explanation:
Given:
Initial velocity of the arrow is, 
The arrow goes up and come back to the same starting position. So, initial position is same as that of final position.
Therefore, displacement of the arrow is 0 m.
The displacement of the arrow is given as:
(equation 1)
Plug all value in equation 1 and solve for 



where 


∴ After 14.92 seconds, the arrow hits the ground.
The product of two perpendicular slopes is always -1