Item 14 sand is added to the timer below so that the height of the sand is 30 millimeters. you must answer a trivia question before the sand in the timer falls to the bottom. the sand falls at a rate of 50 cubic millimeters per second. how much time do you have to answer the question?

the complete question in the attached figure

Volume  of the sand V=(1/3)*h*π*r²

we have that

h=30 mm

r=10 mm

v=(1/3)*30*π*10²=1000≈3140 mm³

the rate is 50 mm³/seg

50 mm³--------------------------------------> 1 seg

3140 mm³-------------------------------- X

x=3140/50=62.8 seg

the answer is 62.8 seg

option (b) is correct

step-by-step explanation:

to find the solution of this system, we need to convert it into reduced row-echelon form. we have,

after applying row operations r2 -> r2/2 and r3 -> r3/3, we get,