When is cos (x) = 0? <em>at 90° (aka π/2)</em>
Answer: 
X : number of tacos they sell per day. ...... profit = y = 3.25 × x - 210 ......inequality. y > 0. so. x > 210/3.25 = 840/13 = 64. ......so the taco stand must sell at least 65 tacos for making profit.
Answer: option J: 128 joules
Explanation:
1) From the table you try to find which relation best fits the data.
2) Your best first assumption is that the data may fit a proportional relation.
3) To prove that you find the ratio of Energy ouput to Amount of chemicals.
Doing that you find:
20 32 48 60
----- = ------- = ------ = ------ = 4
5 8 12 15
4) Then you have found a direct relation whose ratio is 4 joules / mol. So, you can apply that constant to the number of moles given:
Energy = 4 joules / mol × 32 mol = 128 joules
A AsA the angle a and d are equal and side ae and de are egual and angles e are equal
