Answer:
Explanation:
height of pole = 15 ft
height of man = 6 ft
Let the length of shadow is y .
According to the diagram
Let at any time the distance of man is x.
The two triangles are similar

15 y - 15 x = 6 y
9 y = 15 x

Differentiate with respect to time.

As given, dx/dt = 4 ft/s

ft/s
Answer:
2PBr₃ + 3Cl₂ → 2PCl₃ + 3Br₂
2Na + MgCl₂ → 2NaCl + Mg
Explanation:
A balanced chemical equation is a chemical equation that have an equal number of elements of each type on both sides of the equation
Among the given chemical reactions, we have;
2PBr₃ + 3Cl₂ → 2PCl₃ + 3Br₂
In the above reaction;
The number of phosphorus, P, on either side of the equation = 2
The number of bromine atoms, Br, on either side of the equation = 6
The number of chlorine atoms, Cl, on either side of the equation = 6
Therefore, the number of elements in the reactant side and products side of the reaction are equal and the reaction is balanced
The second balanced chemical reaction is 2Na + MgCl₂ → 2NaCl + Mg
In the above reaction, there are two sodium atoms, Na, one magnesium atom and two chlorine atoms on both sides of the reaction, therefore, the reaction is balanced
Explanation:
Polaris also called North star is the brightest star in the the constellation Ursa Minor. It remains stationary whereas entire north sky move around it. It the point of north celestial pole.
A) False. This is because All of the stars move in a counterclockwise path around Polaris.
B) False. Reason stated above.
C) True, As the stars move towards the Polaris there orbital radius decreases as they move smaller circles.
D) False, As the stars move towards the Polaris there orbital radius decreases as they move smaller circles.
E) True.
F) False.
The answer is D.
Hope this helps and have a good day :D