Answer:
It is valid because his experiment had clear variables.
Explanation:
He had clear variables and did everyhting the same for both plants, even though he had calcium in one and not in the other, which gives him a true and good result.
Light travels at precisely <span>299,792,458 metres every second (abbreviated to 3 x 10^8 metres every second but let's be precise)
There are 60 seconds in every minute (</span><span>299 792 458 x 60 = 17,987,547,480m)
60 minutes in every hour (17,987,547,480 x 60 = 1,079,252,849,000m)
96 hours in 4 days (</span><span>1,079,252,849,000 x 96 = 10,360,827,350,000m)
</span><span>Now let's convert to km to make this number (slightly) more manageable
(</span>10,360,827,350,000 / 1000 = <span>103,608,273,500km)
</span>Light travels <span>103,608,273,500km in 4 days - that's the equivalent of going around the equator of the earth 813,124 times!</span><span>
</span>
Endeavour is the youngest shuttle in NASA's orbiter fleet, and was built as a replacement for Challenger. The shuttle flew 25 missions over the course of its spaceflying career, logging a total of 122,883,151 miles (197,761,261 km) on its odometer. Endeavour launched on its maiden flight, STS-49, on May 7, 1992.
Answer:
Sunlight provide light energy.
Chlorophyll absorb light.
Explanation:
Sunlight provide light energy or give light energy from sun and it is use to produce glucose from carbondioxide and water which is also a source of energy.
Chlorophyll absorbs light energy and use it to convert carbondioxide and water into glucose and oxygen or it captures sun rays and produce glucose and water.
Answer : The correct option is, (A) 51.1%
Explanation :
Mass percent : It is defined as the mass of the given component present in the total mass of the compound.
Formula used :
First we have to calculate the mass of 
and 
.
Mass of = 18 g/mole
Mass of 
= 7 × 18 g/mole = 126 g/mole
Mass of = 246.47 g/mole
Now put all the given values in the above formula, we get the mass percent of in .
Therefore, the mass percent of in is, 51.1%
