Answer:
29
Step-by-step explanation:
Simplify the expression
step by step:
1.

2.

Now,

Use these equations when converting polar equations to parametric equations:


We know that
, so substitute that into both equations for x and y.


Now, replace
with any variable that you want to represent the parametric equations in. I'll use the standard variable, 


Thus,
represented in parametric form is:

Let me know if you need any clarifications, thanks!
~ Padoru
The probability of senior citizens suffer from sleep disorders is

The probability of senior citizens suffer from anxiety is,0.09.

The probability of seniors suffer from both sleep disorders and anxiety is,

a. The probability that a senior citizen suffers from anxiety, given that he or she has a
sleep disorder.


Answer: Choice C and Choice D
========================================================
Explanation:
- Choice A doesn't work because it the $1 should be $7 instead.
- Choice B doesn't work because it should be Elena spending $7 total on 3 notebooks and a $1 pen. The x is the amount per notebook.
- Choice C does work. If x is the number of grapes Noah gives each friend, then 3x is the total amount Noah gives over. Then 3x+1 is the number of grapes total. That +1 at the end is the grape Noah eats. We end up with 3x+1 = 7 because Noah starts off with 7 grapes.
- Choice D works also. The x is the number of hours for math, science and history each. So 3x is the combined time of those three classes. Add on 1 to get 3x+1 to represent all 7 hours, ie 3x+1 = 7.
- Choice E does not work. If it was her spending $7 on 3 markers and a $1 pen, then it would work.