The elevation of Dallas, Texas, is 430 feet. Which of the following best describes 430 feet? A.
215 feet above sea level
B.
215 feet below sea level
C.
430 feet below sea level
D.
430 feet above sea level

Elevation describes the height above (or below) sea level.  But if it's below sea level, the you would say "430 feet below sea level."  It's assumed to be above, unless you say otherwise.

D

430 feet above sea level

anwser D

Step-by-step explanation:

450 is the final answer! : )

since the airplane is moving with constant speed then the distance travelled can be calculated by x=u*t

in km/h would be:

x=640*3.5=2.240 km

in m/s would be:

u=640 km/h= 640.000 m/h =640.000/ 3600 m/s =177.8 m/s

t= 3.5 h= 3.5 * 3600 s=12.600 s

then x=u*t= 177.8*12.600= 2.240.280 m