Answer:
see explanation
Step-by-step explanation:
The sum of the 3 angles in a triangle = 180°, thus
∠1 = 180° - (72 + 57)° = 180° - 129° = 51°
The right angle at the left vertex is composed of 72° and ∠2, thus
∠2 = 90° - 72° = 18°
57° and ∠3 form a straight angle and are supplementary, thus
∠3 = 180° - 57° = 123°
∠4 = 180° - (∠2 + ∠3 ) ← sum of angles in a triangle
∠4 = 180° - (18 + 123)° = 180° - 141° = 39°
Answer:
C
Step-by-step explanation:
The volume of a cone is given by 
The volume of a cylinder is given by 
<em>Where h is the height and r is the radius</em>
The first figure is a cone with height 6 and radius 5, we can put it into the formula and find the volume:

The second figure is a cylinder with height 50 and radius 1, we can put it into the formula and find the volume:

We can see that they are equal. So answer choice C is right.
Four hundred twenty-three billion, ninety million, seven hundred nine thousand
Hope this helped:))
Answer:
160
Step-by-step explanation:
400 / 2.5 = 160
160 x 1 = 160
Answer:
t < 1.5
Step-by-step explanation:
Mon-Thu: 5.5 hours
each of the remaining 3 days: t hours each day
total time: 3t + 5.5
The total time must be less than 10 hours.
3t + 5.5 < 10
3t < 4.5
t < 1.5