Answer:
none of the above
Step-by-step explanation:
cohen's d= (Mean of population - mean of sample)/ standard deviation of population
0.5 = (80-mean of sample)/12
Mean of sample= 74
Answer:
1. 
2 a) 
b) 0
3. x = 10
Step-by-step explanation:
1.

2. a)
![2 [(\frac{-1}{4}) -12 (-1)^2] - 5[24 +2 (-12)]^2\\2[(\frac{-1}{4}) -12] - 5[24 -24]^2\\2 * [(\frac{-1}{4}) -12] -0\\\frac{-49}{2}](https://tex.z-dn.net/?f=2%20%5B%28%5Cfrac%7B-1%7D%7B4%7D%29%20-12%20%28-1%29%5E2%5D%20-%205%5B24%20%2B2%20%28-12%29%5D%5E2%5C%5C2%5B%28%5Cfrac%7B-1%7D%7B4%7D%29%20-12%5D%20-%205%5B24%20-24%5D%5E2%5C%5C2%20%2A%20%5B%28%5Cfrac%7B-1%7D%7B4%7D%29%20-12%5D%20%20-0%5C%5C%5Cfrac%7B-49%7D%7B2%7D)
b)

3.

Answer:
the answer is X > 9
Step-by-step explanation:
you divide move the 2 to the other side and divide by 18
The question asks for sales tax rate. Sales tax is 39.90-38=1.90 and that's taxed onto the original $38 so 1.9/38=0.05
5% tax on the blazer
I know that the answer for number 10 is the first option