Lucy wants to divide 18.6 by 1.2 in order to estimate the quotient which is the best expression to use ? a: 10÷1 b: 10÷2 c: 20÷1 d: 20÷2

Option C is the best expression.

Step-by-step explanation:

We are asked to find 18.6 by 1.2.

Option A

     10÷1 = 10

     Difference = 15.5 - 10 = 5.5

Option B

     10÷2 = 5

     Difference = 15.5 - 5 = 10.5

Option C

     20÷1 = 20

     Difference = 20 - 15.5 = 4.5

Option D

     20÷2 = 10

     Difference = 15.5 - 10 = 5.5

So, the difference is minimum for option C

Option C is the best expression.

the distance from any point on the parabola to the focus is the exact same as the distance from that point to the directrix.

if you could provide answer choices that might allow me to answer the question easier if my above answer isn't an option! (:

check the picture below.

well, the angle at the vertex d is clearly not a right-angle, let's check for the one at the vertex f which does look like,   however if it's indeed, that means ef is perpendicular to df, in which case their slopes will be negative reciprocal of each other.

so the negative reciprocal of the slope of ef is 1, however the slope of df is not 1, is 1/2, so nope, they're not perpendicular lines.