Answer:
Scientific Notation: 3.45 x 10^5
E Notation: 3.45e5
Answer: 3.33 m/s
Explanation:
Assuming the questions is to convert 12 km/h to meter per second (m/s), let's begin:
In order to make the conversion, we have to know the following:

And:

Keeping this in mind, we can make the conversion:

Then:

Answer:
t = 13.7 s or t = 14 s with proper significant figures
Explanation:
The initial speed is 0 m/s since the car starts from rest, acceleration is 5.5 m/s2 and distance is 523 m.
Since we have initial speed, acceleration and distance we can use the following formula to find the time. We can now use algebra to work out our answer.
d = vt +
at²
523 = (0)t + (
)(5.5)t²
523 = 2.8t²
186.8 = t²
13.7 s = t
(t = 14 s with proper significant figures)