12/X=X/6
X^2=72
X= 8.48
X=8.5
18/y=y/12
Y-^2= 216
Y= 14.69
Y= 14.7
To convert mi/h to ft/sec, multiply it to 1.466.
So 3.4 mi/h x 1.466 = 4.986 ft/sec
E, because he is stealing everything, meaning he has a net profit. So, you would add everything. Since he 280 $1 bills, he just stole $280 which is a definite quantity, so we don't need a variable for it. Since everything else are indefinite quantities, we need variables (x, y, z). But, yeah, E should be the answer.
You can tell based off the translation of graphs.
Vertical:
y=f(x) + k : graph shifts k units up
y=f(x) - k : graph shifts k units down
Horizontal:
y=f(x - k) : graph shifts k units right
y= f(x+k) : graph shifts k units left
