Answer: a) Unimodal and symmetric
b) 0.26
c) 0.038
Step-by-step explanation:
Given: Sample size of investors (n)= 131
True proportion of smartphone users(p) =26%
a) Since sampling distribution for the sample proportion is approximately normal when n is larger.
Normal distribution is Unimodal and symmetric.
So correct option : Unimodal and symmetric
b) mean of this sampling distribution = p = 0.26
c) standard deviation of the samplingdistribution = 

Mowing 4 lawns in 6 hours gives a mowing rate of 6/4 = 1.5 hours per lawn.
To mow 9 lawns, you need 1.5*9 = 13.5 hours.
The answer is B.
Answer:
10 km/h
Step-by-step explanation:
First, convert 150 minutes to hours:
150/60
= 2.5 hours
Then, to find his speed, divide the km by the number of hours:
25/2.5
= 10 km/h
Answer:
Choices C and D
Step-by-step explanation: