we can use formula

where
fL is listener frequency
fs is siren frequency
va is the speed of sound in air
vs is police car speed
so, we have



now, we can change it into m/s


now, we can plug it

..............Answer
Answer:
B
Step-by-step explanation:
Think of it like a quarter you got a half and half shot if getting heads or tails. meaning a 50/50 chance.
He would’ve sold 12 candy bars.
12x3=36
He only sold 20 items so that leaves 8 cookies
5x8=40
40+36=76$
The perimeter of a rectangle si length + length + width + width or 2l + 2w. Substitute your values in to get 2(70) + 2(65) → 140 + 130 → 270 feet
I believe its the second one because it say four times the number wich the number is the y and it is = too the number wich is y and increased going up are adding by 9. hope that helped.