Answer:
c
Step-by-step explanation:
because that would be the wrong one
The ratio is 4:3:1
let the ratio be 4x:3x:x
according to the question,4x+3x+x=40
8x=40
x=5
therefore amount of gravel=x*4=5*4=20

amount of sand=5*3=15

amount of cement=5*1=5
Your answer should be B !
Phoebe is correct. The line on the graph would be vertical in the x-axis value of 12.