Answer:
time taken with speed 23 km/h will be 1.8 hours or 1 hour 48 minutes
Explanation:
Given:
Time is inversely proportional to the speed
mathematically,
t ∝ (1/r)
let the proportionality constant be 'k'
thus,
t = k/r
therefore, for case 1
time = 3 hr
speed = 14 km/hr
3 = k/14
also,
for case 2
let the time be = t
r = 23 km/h
thus,
we have
t = k/23
on dividing equation 2 by 1
we get

or

or
t = 1.8 hr = or 1 hour 48 minutes ( 0.8 hours × 60 minutes/hour = 48 minutes)
True
A scientific law only states that an event occurs.
Hope this helps!
Answer:
When Helium is identified by astronomers is one of the great triumphs of spectroscopy.
Explanation:
Janssen managed to do this great triumphs on August 18, 1868 . Janssen was the first person to introduce the helium, an element that never seen before on Earth, in the solar spectrum. At that time, he didn’t know that what he’d seen—he just think that it was something new. In the mid of 1800, the spectroscope instrument is introduced in astronomy.
Later on we heard that all helium in Universe has been created by the fusion of hydrogen nuclei.
To know more about Spectroscopy:
brainly.com/question/14677550
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Explanation:
Average speed = change in distance / change in time
In other words, the average speed is the slope of the line connecting two points on the graph.