Answer:
a) f = 453.3Hz
b) f = 443.1Hz
c) f = 420Hz
Explanation:
First of all we need to know the positions and velocities of both vehicles.
For the car:
Xc(-5) = 0m; Vc(-5) = 0m/s
; Vc(5)=2.5*5 = 12.5m/s
; Vc(10)=2.5*10=25m/s
For the truck:
Xt(-5)=10*(-5) = -50m; Vt(5)=10m/s
Xt(5)=10*5 = 50m; Vt(5)=10m/s
Xt(10)=10*10=100m; Vt(10)=10m/s
Now for part a) t=-5s. The truck is behind the car, so:

Now for part b) t=5s. The car is behind the truck, so:

Now for part b) t=10s. The truck is behind the car, so:

Answer:
speed =wavelenght x frequency
v=4.5 x 10 to the -7 x 667=0.3 x 10 to the -4 m/s
speed= distance/time
time=distance/speed
t=4 x 10 to the 16/0.3 x 10 to the -4=13.33 x 10 to the 20 seconds
Explanation:
Lighting gives a sense of scale (The sky)
The number 4 represents four atoms of iodine per molecule. Thyroxine is a type of hormone produced by the thyroid gland and this hormone controls human's metabolism process. There are two hormones produced by the thyroid gland, the thyroxine and the triiodothyronine, which also control human's metabolism process. These hormones consisted of iodine atoms in each of the molecule, which human gets from eating salt.
If you count the number of seconds between the flash of lightning and the sound of thunder, and then divide by 5, you'll get the distance in miles to the lightning: 5 seconds = 1 mile, 15 seconds = 3 miles, 0 seconds = very close. Keep in mind that you should be in a safe place while counting.