The true answer here is B.
Magnitude of momentum = mass*velocity = 480*40 = 19200 kg/km/hr
Answer:
260
Step-by-step explanation:
A = bh
Consider a set M, and an operation *.
Let a and b be in M, then M is closed under operation * if :
a*b, and b*a produce an element of M
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The set of negative numbers (set M) is not closed under subtraction (the operation *).
Consider 2 numbers a=-9 and b=-6 which certainly are in M.
-9*(-6) = -9-(-6)=-9+6=-3 ∈ M (note that * is the regular subtraction -)
(-6)*(-9)=-6-(-9)=-6+9=3 ∉ M