The angle of prism is 41.81 degrees.
<u>Explanation:</u>
For no emergence to be taken place, inside a prism, Total Internal Reflection (TIR) should take place at the second surface. For TIR, at second surface, angle of refraction must be greater than critical angle. Angle of prism is related to refraction as,

Since,
= C and 
This implies 



when sin goes to other side become as sin inverse of value, and obtain the result as below,

The answer is B because it's 80 percent copper, that's a greater number then 20.
4. The core is where fusion occurs when Nuclear Thermal Fusion happens, which means the core is fusing hydrogen to create helium. This energy passes through both the convection and radiation zone. If you need any more help with this subject, I'll be able to help.
Answer:
The distance is
=
7
m
Explanation:
Apply the equation of motion
s
(
t
)
=
u
t
+
1
2
a
t
2
The initial velocity is
u
=
0
m
s
−
1
The acceleration is
a
=
2
m
s
−
2
Therefore, when
t
=
3
s
, we get
s
(
3
)
=
0
+
1
2
⋅
2
⋅
3
2
=
9
m
and when
t
=
4
s
s
(
4
)
=
0
+
1
2
⋅
2
⋅
4
2
=
16
m
Therefore,
The distance travelled in the fourth second is
d
=
s
(
4
)
−
s
(
3
)
=
16
−
9
=
7
m