Help plz A sphere is rolled between two sharp, parallel blades that are 77 centimeters apart. Both blades cut off a piece of the sphere cleanly, leaving two parallel circular faces with radii of 39 and 60 cm. What is the radius of the sphere?

The radius of the sphere is approximately 62.71 cm

Step-by-step explanation:

The question relates to the definition of a sphere

The given parameters are;

The distance between the sharp parallel blades through which the sphere is rolled = 77 centimeters

The radii of the circular faces left by cutting the sphere with the blade = 39 cm  and 60 cm

From the triangles formed by the cross-section of the sphere, we have;

AB ║ DE Given

∠A ≅ ∠E, ∠D ≅ ∠B Alternate angles

∠C ≅ ∠C by reflective  property

∴ ΔABC ~ ΔDCE by Angle-Angle similarity theorem

CF/CG = AB/DE = 78/120 = 13/20

CF = CG × 13/20

CF + CG = 77

∴ CG × 13/20 + CG = 77

33·CG/20 = 77

∴ CG = 140/3

CF = 13/20 × CG = 13/20 × 140/3 = 91/3

CF = 91/3

The diameter of the sphere AE = AC + EC

By Pythagoras's theorem

AC = √(FA² + CF²) = √(39² + (91/3)²) = 13·√(130)/3

EC = √(CG² + GD²) = √((140/3)² + 60²) = 20·√(130)/3

∴ AE = AC + EC = 13·√(130)/3 + 20·√(130)/3 = 11·√(130)

The diameter, 'D', of the sphere, AE = 11·√(130)

The radius of the sphere = D/2 = 11·√(130)/2 ≈ 62.71 cm

the clues that signal the reader should change tone are the punctuation marks, the grammatical signs. for example, the quotation marks at the beginning of something someone else said literally or the exclamation marks.

the tone of the first line of dialogue until "gettysburg" is a kind tone, a tone of advise. the narrator is trying to the other person in doing something he or she obviously is finding hard to do by giving a piece of advise and bringing up a memory of a successful similar case.

the clue that the reader understand how to read the word "bang" is the exclamation mark. it gives the word a surprise tone, a strong accent.

the best tone for reading the word "bang" is an exciting tone, a surprise one, even a loud one.

the words that should be read with a formal tone are the ones that give factual information. the sentence: mister lincoln couldn't think of anything to say at the gettysburg" gives information about an event and it needs to be read formally, also, when the narrator wants to transmit calmness, a formal and slow tone is needed, because people also transmit messages with the vibrations of our voices and tones.

21

jk it's 20

step-by-step explanation: