Answer:
"When face is placed between the concave mirror and its focus, it produces a magnified image. This enlarged image of face is helpful in makeup as even pores of skin are clearly visible."
Average speed = (distance covered) / (time to cover the distance)
Average speed = (1.6 km) / (30 min)
Average speed = 0.0533 km/min
This is the true average speed, but it's not in the units that the question asked for. So we have to massage it and convert it to ' meters/sec '.
Speed = (1.6 km) / (30 min)
Speed = (1.6 km / 30 min) x (1,000 m / 1 km) x (1 min / 60 sec)
Speed = (1.6 x 1,000 x 1) / (30 x 1 x 60) (km-m-min / min-km-sec)
Speed = (1,600 / 1,800) (m / sec)
<em>Speed = 0.89 m/s </em>
The acceleration due to gravity varies in different positions on Earth. However it is said to be negligible and 9.8 m/s is used. Sometimes people use 10 m/s or 9.81 m/s
(1,500 meters) x (1 sec / 330 meters) = (4 and 18/33) seconds
(4.55 sec, rounded)