Metal cylindrical disc of base radius 20 cm in height 7 cm is melted and recast into a cylindrical lock of base radius 14 cm find the length of cylindrical block also find the ratio when the total surface area of the cylinder is to the block

Step-by-step explanation:

The initial metal cylindrical disc has a base radius of 20 cm and height of 7 cm.

The formula for determining the volume if a cylinder is expressed as

Area = πr^2 h

Where

π is a constant whose value is 3.14

r represents radius of the cylinder.

h represents height of the cylinder.

Volume of the metal cylindrical disc

= π × 20^2 × 7 = 2800π cm^3

The metal cylindrical disc is melted and recast into a cylindrical lock of base radius 14 cm

Volume of the cylindrical lock would also be 8792 cm^3. Therefore,

2800π = π × 14^2 × l

l = 2800π/196π = 14.29 cm

Formula for determining total surface area of a cylinder is expressed as

2πrh + 2πr^2

Total surface area of the metal cylindrical disc would be

(2 × π × 20 × 7) + (2 × π × 20^2)

280π + 800π = 1080π cm^2

Total surface area of the cylindrical block would be

(2 × π × 14 × 14.29) + (2 × π × 14^2)

400.12π + 392π = 792.12 cm^2

The ratio of the total surface area of the cylinder to the block would be

1080/792.12 = 1.36

option a.

step-by-step explanation:

if you look closely at the graph, we can notice that the function is not defined at two different points.

if you look at functions b and c, you will notice that both functions are not defined at just one point. the function b is not defined at x= -5/2 and function c is not defined at x=-5. both options are discarded, given that our function should not be defined at two fiferent points.

now, if you look closely at the graph you will notice that the function sketched is not defined at x=5 and x=-2.

24

step-by-step explanation:

if it takes 8 pounds to make 12 divide 12 by 8 and you get 1.5, 1.5 x 16 = 24