<span>What you need to do while answering this questions, is ask yourself what has cells - only if a thing has cells can you see those cells under a microscope. Objects of animal and plant origin have cells, so blood, plant and cork (made of tree bark) can have cells, and a box too, if it's made of wood. So we can''t exclude any answers based on this. We must then know the story of Robert Hook - and it was in fact a cork. He did this discovery around 1655. At the time his main interest was the microscope rather than the cork, and he used to cork to demonstrate the function of the microscope. The correct answer is CORK.</span>
Answer:
i think it would be B. Aluminum, Al and D. Boron, B
Explanation:
since they're both in group 13 and they forms a 3+ ion
Given speed and the distance that must be covered, the time it will take the ultraviolet light to reach the earth is 3.7 × 10⁴ hours.
<h3>
What is Speed?</h3>
Speed is simply referred to as distance traveled per unit time.
Mathematically, Speed = Distance ÷ time.
Given the data in the question;
- Speed of the Ultraviolet light c = 3.0 × 10⁸m/s = 1.08 × 10⁹km/h
- Distance it must cover d = 4.0 × 10¹³km
We substitute our given values into the expression above.
Speed = Distance ÷ time
1.08 × 10⁹km/h = 4.0 × 10¹³km ÷ t
t = 4.0 × 10¹³km ÷ 1.08 × 10⁹km/h
t = 3.7 × 10⁴ hrs
Therefore, given speed and the distance that must be covered, the time it will take the ultraviolet light to reach the earth is 3.7 × 10⁴ hours.
Learn more about speed here: brainly.com/question/7359669
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Explanation:
It is given that,
Velocity of the particle moving in straight line is :
We need to find the distance (x) traveled by the particle during the first t seconds. It is given by :
Using by parts integration, we get the value of x as :
Hence, this is the required solution.
