1. formula:
velocity=distance/time
velocity is 80km/hr
time=18mins. or 0.3hr
substitute the given,.
distance=80×0.3=2.4 km....is the answer.
2. area=∏r^2
314=∏r^2
radius=9.9975 or say 10
circumference=2∏r
=2∏(10)
=62.816 cm
3. still unsolved..
but the two problems are correct..