Answer:
lanthanide and actinide
Explanation:
An inner transition metal (ITM) of chemical elements on the periodic table. They are normally shown in two rows below all the other elements. They include elements 57-71, or lanthanides, and 89-103, or actinides.
Answer:
The magnification is 
Explanation:
From the question we are told that
The power of the lens is 
Generally 
The object distance is 
the negative sign is because the distance is measured in the opposite direction of incident light (i.e away )
Generally the focal length is mathematically represented as
=>
=> 
converting to cm
=> 
Generally from lens equation we have that
=> 
=> 
Generally the magnification is mathematically represented as
=> 
=>
<span>t^2 = 1/4.9 </span>
<span>t = 0.45 sec
answer:</span><span>1 - 4.9t^2 = 0 </span>
Explanation:
We know that the sky appears to us like a sphere called as celestial sphere which appears to rotate around an imaginary axis because of Earth's rotation. Since the axis cuts the celestial sphere at celestial poles all the object seems to circle around the celestial poles.
Condition 1: The stars rise and set perpendicular to the horizon
The observer is at the equator
Condition 2: The stars circle the sky parallel to the horizon
The observer is at the Pole of the Earth
Condition 3: The celestial equator passes through the zenith
The observer is at the equator
Condition 4: In the course of a year, all stars are visible
The observer is at the equator
Condition 5: The Sun rises on March 21 and does not set until September 21 (ideally)
The observer is at North Pole
