a) How fast is she running in m / s?
The first thing you should know for this case is the following conversion
1mi = 1609.34m
1h = 3600s
Applying the conversion
4.20 (mi / h) * (1609.34 / 1) (m / mi) * (1/3600) (h / s) = 1.88 m / s
answer
She is running 1.88 in m / s
(b) how many kilometers does she run in 33.0 min?
By definition, the distance equals the speed by time
d = v * t
Also,
1min = 60seconds
1 km = 1000 meters.
We have then
d = (1.88) * (33) * (60) * (1/1000) = 3.72 Km
answer
she run 3.72 Km in 33.0 min
(c) if she starts a run at 11:15 a.m., what time is it after she covers 4.84 × 104 ft? : p.m.
The first thing we need to know is the following conversion
1Km = 3280.84 feet
We have then
3.72 (Km) * (3280.84 / 1) (feet / Km) = 12204.73 feets
I have the following rule of three we can know how long she travels 4.84 × 104 ft
12204.73 feets ----> 33 min
4.84 * 10 ^ 4 feets ----> x
Clearing x:
x = ((4.84 * 10 ^ 4) / (12204.73)) * (33) = 131 min
131 min = 2:11:00 hours
she starts a run at 11:15 a.m.
she finishes at
1:26 p.m.
answer
it is 1:26 p.m when she covers 4.84 × 104 ft
