Olivia works at a company that creates mobile phones. She wanted to estimate the mean amount of time their new phone's battery lasts with regular use after a full charge. She took a random sample of 6 of these phones and randomly assigned each of them to a volunteer. She instructed them to fully charge the phones and use them as they regularly would until the battery died (without recharging the phone). Here are the data they reported: Assume that all conditions for inference are met.
Which of the following is a 90% confidence interval for the mean battery life (in hours)?

24

step-by-step explanation:

the graph shows 30% of students walk. 80 students were questioned, so the number that said they walk is

30% × 80 = 0.30 × 80 = 24

answer: first option i.e. 'a' is correct.

step-by-step explanation:

since we have given that

number of minutes to wrap a small gift box = 4 minutes

we need to find the number of gifts to be wrapped in 5 minutes

since there is a direct variation, as the number of minutes will increase with   number of gifts to be wrapped.

so, let the number of gifts to be wrapped in 5 minutes be x.

so, it becomes,

hence, first option 'a'   is correct.

answer: 7. if the functions had a negative leading coefficient and is of even degree, which statement about the graph is true?

step-by-step explanation: