Answer:
Q (heat) = S * m * (T2 - T1) where Q is heat gained (loss), S the specific heat capacity of the substance and T2, T1 are the final and initial temps
Q = .215 cal / (g deg C) * 5 g * (20 - 80) deg C = -64.5 cal
Since the question specifies the heat emitted, then 64.5 cal is the
heat emitted (loss).
the answer is waning Gibbous
The Waning Gibbous is an intermediary Moon phase. It starts right after the Full Moon, and it lasts until the Third Quarter.
Answer:
Star A is brighter than Star B by a factor of 2754.22
Explanation:
Lets assume,
the magnitude of star A = m₁ = 1
the magnitude of star B = m₂ = 9.6
the apparent brightness of star A and star B are b₁ and b₂ respectively
Then, relation between the difference of magnitudes and apparent brightness of two stars are related as give below: 
The current magnitude scale followed was formalized by Sir Norman Pogson in 1856. On this scale a magnitude 1 star is 2.512 times brighter than magnitude 2 star. A magnitude 2 star is 2.512 time brighter than a magnitude 3 star. That means a magnitude 1 star is (2.512x2.512) brighter than magnitude 3 bright star.
We need to find the factor by which star A is brighter than star B. Using the equation given above,



Thus,

It means star A is 2754.22 time brighter than Star B.
Answer:
ω₂=1.20
Explanation:
Given that
mass of the turn table ,M= 15 kg
mass of the ice ,m= 9 kg
radius ,r= 25 cm
Initial angular speed ,ω₁ = 0.75 rad/s
Initial mass moment of inertia



Final mass moment of inertia



Lets take final speed of the turn table after ice evaporated =ω₂ rad/s
Now by conservation angular momentum
I₁ ω₁ =ω₂ I₂

ω₂=1.20