Answer:
1:
<A=½(arcJL)=½(70+120)=35+60=95°
[inscribed angle is half of central angle]
2:
<W=½arcVX=½(130)=65°
[inscribed angle is half of central angle]
3.
<E=½(arcDC)=½(90)=45°
[inscribed angle is half of central angle]
4.
<R=½(arcXZ)=½(110+62)=86°
[inscribed angle is half of central angle]
5.
<B=½(arc DC)=½×104°=52°
[inscribed angle is half of central angle]
6.
<K=90°
[inscribed angle in a diameter is complementary]
<K+<J+<L=180°(sum of interior angle of a triangle]
<L=180°-90°-53°=37°
again
arc JK=2×<L=2×37=74°
Answer:
h=30cm
Base sides, x=30cm
Step-by-step explanation:
Let x be the dimension of the sides and h the dimension of height;

#Material used is directly proportional to surface area. Minimizing surface area will minimize the amount of material used.

Find area as a function of x:

To minimize Area, we find the first derivative of Area:

#find the second derivative to verify the minimum:

Substitute x in the volume equation to find h:

Hence, the dimensions of the box that minimize the amount of material used h=30cm and x=30cm