Which set is closed under subtraction?

If the measure of angle 1 is 110 degrees and the measure of angle 3 is (2 x+10 degree), what is the value of x?

Jonathan can type 20 documents in 40 minutes ,and susan can type it in 30 minutes and jack can type it in 24 minutes working together ,how much time will it is take them type the same document

People end up tossing 12% of what they buy at the grocery store. assume this is the true population proportion and that you plan to take a sample survey of 540 grocery shoppers to further investigate their behavior. a. calculate the mean and the standard error for the sample proportion p. b. describe the sampling distribution of p in part a. draw a graph of this probability distribution with its mean and standard deviation. what is the probability that your survey will provide a sample proportion more than 15%? c. d. population proportion? what is the probability that your survey will provide a sample proportion within + 0.03 of the