Answer:
20
Step-by-step explanation:
Answer:
252
Step-by-step explanation:
The question is fully equivalent to asking how many subsets of length 5 there are of 10 objects (digits 0–9). That number is 10C5, where nCk is the number of ways to choose k objects from a list of 10. The value of that is ...
nCk = n!/(k!(n-k)!)
There are 252 ways to choose 5 numbers from the digits 0-9:
10C5 = 10!/(5!(10-5)!) = 10·9·8·7·6/(5·4·3·2·1) = 9·4·7 = 252
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The order of the selection doesn't matter, because the selected digits are always arranged in decreasing order to form a decreasing number.
Answer:
F
Step-by-step explanation:
Answer:
The answer is a
Step-by-step explanation:
The distance from the near end of the runway to the plane, divided by the altitude is the tangent of (90 degrees minus the angle of depression). Let "d1" be the distance to the near end of the runway, and "d2" be the distance to the far end of the runway. Let "a" be the altitude of the plane.
d1/a = tan(90 - 31)
d1 = a*tan(90 - 31)
d2/a = tan(90 - 23)
d2 = a*tan(90 - 23)
runway length = d2 - d1 = a*(tan(67) - tan(59))
length = 1800*(.6916) = 1245m = 1.2km
the answer is "a"
