9) yes, he is correct.
50% as a decimal would be 0.50
7% as a decimal would be 0.07
10)Buy and Bye has a greater discount because 30% as a decimal is 0.30 and 1/4 as a decimal is 0.25.
0.30 is bigger than 0.25 so it is a bigger discount
Given that

, then

The slope of a tangent line in the polar coordinate is given by:

Thus, we have:

Part A:
For horizontal tangent lines, m = 0.
Thus, we have:

Therefore, the <span>values of θ on the polar curve r = θ, with 0 ≤ θ ≤ 2π, such that the tangent lines are horizontal are:
</span><span>θ = 0
</span>θ = <span>2.02875783811043
</span>
θ = <span>4.91318043943488
Part B:
For vertical tangent lines,

Thus, we have:

</span>Therefore, the <span>values of θ on the polar curve r = θ, with 0 ≤ θ ≤ 2π, such that the tangent lines are vertical are:
</span>θ = <span>4.91718592528713</span>
Without scientific notation<span> it would look like 4 000 000 000 000 </span>
<span>The decimal place must be moved 12 units to the left to be after a significant figure, thus giving the scientific notation to the power of 12. The significant figure is 4 so you get the equation </span><span>4.0⋅<span>1012</span></span>.
<span>
</span>
To find the incompleted portion of the test, convert the decimal to a percentage by moving the decimal two places to the right. .7 as a percentage is 70%. subtract 70% from 100%, giving you 30%. Juan has not completed 30% of his test, or 5 questions.