Let height of twin falls = x
height of seven falls = 2.5x
x + 2.5x = 420
3.5x = 420
x = 420/3.5 = 120
so twin falls = x = 120 ft
seven falls = 2.5x = 300 ft
B) It’s material moves due to convection currents.
just search up the answer/ definition to all of them, rephrase into own words, then do the same for examples.
150*4=600
So the answer is 600
I think you can just sub the values in? unless the qn is asking for smth else?