Answer:

Step-by-step explanation:
we know that
The density is equal to the mass divided by the volume
Let
x-----> the mass of marble
y----> the volume of marble
z----> the density of marble

in this problem we have


substitute and solve for x


Answer:
River D: 2780 River C: 2280
Step-by-step explanation:
Please mark brainliest
Answer: 1) 8/15 2) 2 4/9 3) -13/45
Step-by-step explanation:
1/5 + 1/3 = 6/30 + 10/30 = 16/30 = 8/15
2 1/9 + 1/3 = 19/9 + 3/9 = 22/9 = 2 4/9
1/9 - 2/5 = 5/45 - 18/45 = -13/45
1/2 of 14 is 7 so 7th x plus 8th x = 30+30 / 2 = the median is 30