Answer:
1 : 64
Step-by-step explanation:
Model:
1/2 in * 1/6 in = 1/12 in^2
Real:
1/3 ft * 1/9 ft = 1/3 * 12 in * 1/9 * 12 in = 16/3 in^2
model : real
1/12 / 16/3 = 1/12 * 3/16 = 3/192 = 1/64
model : real = 1 : 64
You can by filling 1 out of 4 bars then multiply the shaded bars by 3<span />
For any equation,

assume solution of a form, 
Which leads to,

Simplify to,

Then find solutions,

For non repeated real root y, we have a form of,

Following up,
For two non repeated complex roots
where,

and,
the general solution has a form of,

Or in this case,

Now we just refine and get,

Hope this helps.
r3t40
The first one is b. The second one is d. Sorry if I’m wrong :(
are your O's different sizes? or is it just my eyes?