<PRE><B>Question 205628</B>
At the moment when its altitude is 300 m, a plane is flying with a horizontal
 speed of 200km per hour and an unknown vertical speed. What is the minimum
 average vertical speed,in km/hr, required to avoid a 500 m tall mountain
 situated at a horizontal distance of 1km away from the plane?
:
Plane required to gain 500 - 300 = 200 meters
:
Determine how many seconds the plane is from the mountain at a horizontal speed of 200 km/hr.
:
{{{1/200}}} * 3600 = 18 sec 
:
Find the vertical speed required to go up 200 meters, in km/hr
{{{200/18}}} * 3600 * {{{1/1000}}} = 40 km/hr vertical speed (minimum)  
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