Answer: 

Step-by-step explanation:
- A null hypothesis is a hypothesis where a researcher generally try to disprove, it says that there is no statistically significant relationship between the two variables .
- An alternative hypothesis says that there is a statistical significance between two variables.
Claim 1. : Mean age of online dating service users is 40 years.
i.e.
, since it has equals sign so we take this as null hypothesis.
Claim 2. : Mean age of online dating service users is not 40 years.
⇒ Null Hypothesis : 
Alternative hypothesis : 
Answer:
1. attachment↑
its grade 8
Step-by-step explanation:
mark me as brainliest if it helps
The mistake is line 4, she should have divided 42 by 5, not add 5 and 16
Answer:
sorry dont know
Step-by-step explanation:
Answer:
27
Step-by-step explanation:
Lets find the rate of selling:
Let v= the rate of selling, b = number of bottles of water, and t = time:
b over t gives us the
rate of selling:
3 hours is 60min * 3 = 180 mins, and since v=b/t, vt=b:
(0.15) * 180 = 27 bottles of water