In dry air the sound travels with 331,2 m/s
in 3*10^10 the distance will be 3*331,2*10^10 m=9936*10^9 m=9936*10^6 km
3 divided by 12 equals 0.25
So we change 0.25 to a fraction which is 1/4
The probability is 1/4
The maximum or minimum occurs when x is at the axis of symmetry
it will be a maximum since h(x) opens upward (a>0)
to find the axis of symmetry
h= -b/2a (ax^2 +bx+c) so b=-12 and a=3
h = -(-12)/2(3) = 12/6 = 2
x=2