19. An engine has enough fuel to operate at full power for 20 minutes. For how long could the engine operate at 35% of full power?

57.1428 minutes

Step-by-step explanation:

Power : Time

100 : 20

35 : x

if POWER increase then TIME decrease, it means both are inversely proportional to each other

x/20 = 100/35

x = (100/35) * 20

x = 400 / 7

x = 57.1428

where x is basically the time in minutes, So time = 57.1428 minutes

for 5 minutes

Explanation:

35%/ 100 20 times 5 is 100. so I thought it would be 5

answer: the answer is (b) amie should have multiplied

step-by-step explanation: given a sphere and a cylinder with same radius and height.

let, 'r' be the radius of the cylinder and sphere and 'h' be the height of the cylinder. according to the question,

r = h.

now, the volume of the sphere will be

and the volume of the cylinder will be

therefore, we have

thus, ammie should have multiplied the volume of the sphere

answer

d. 10

explanation

the distance from point y to wx is the height of the triangle.

using pythagoras theorem,

group similar terms to get,

this implies that,

take positive square root of both sides to get,

this implies that,