Answer:
40 hours
Step-by-step explanation:
Lets take "x" as the # of hours it takes the lava to reach the sea
since there is a lava flow of 0.5 kilos per hour
we will multiply "x" with 0.5
0.5x
now the tube system is 20 kilometers long
this means that at a rate of 0.5 kilos per hour the lava will reach the sea once it is 20 kilometers deep
so
0.5x=20
divide "0.5" by both sides to eliminate the coefficient

x=40
it will take 40 hours for the lava to reach the sea
Hope this helps!
Answer:
Melissa
Step-by-step explanation:
Melissa: 18/20
Tom: 85/100
Find the common denomenater so multiply 18*5 and 20*5
Melissa: 95/100
95>85
Melissa has the greater mark
3m² = 3 - 8m
0 = 3m² + 8m - 3
0 = (3m - 1 )(m + 3)
m = -3, 0.33
Using a proportional relationship, it is found that the two equations that have the same constant of proportionality are givn by:
с 1 and 3
<h3>What is a proportional relationship?</h3>
A proportional relationship is a function in which the output variable is given by the input variable multiplied by a constant of proportionality, that is:
y = kx
In which k is the constant of proportionality.
In this problem, the functions and constants are given as follows:
- 3. 8y = 6x -> k = 6/8 = 3/4.
Equations 1 and 3 have the same constants, hence option c is correct.
More can be learned about proportional relationships at brainly.com/question/10424180
Answer:
C
Step-by-step explanation: