I have no doors but I have keys, I have no rooms but I do have a space, you can enter but you can never leave. What am I?

Stocks a, b, and c are similar in some respects: each has an expected return of 10% and a standard deviation of 25%. stocks a and b have returns that are independent of one another; i.e., their correlation coefficient, r, equals zero. stocks a and c have returns that are negatively correlated with one another; i.e., r is less than 0. portfolio ab is a portfolio with half of its money invested in stock a and half in stock b. portfolio ac is a portfolio with half of its money invested in stock a and half invested in stock c. which of the following statements is correct? a. portfolio ab has a standard deviation that is greater than 25%.b. portfolio ac has an expected return that is less than 10%.c. portfolio ac has a standard deviation that is less than 25%.d. portfolio ab has a standard deviation that is equal to 25%.e. portfolio ac has an expected return that is greater than 25%.

Presented below is information for annie company for the month of march 2018. cost of goods sold $245,000 rent expense $ 36,000 freight-out 7,000 sales discounts 8,000 insurance expense 5,000 sales returns and allowances 11,000 salaries and wages expense 63,000 sales revenue 410,000 instructions prepare the income statement.

Noah met an old friend at a coffee shop. he jotted down the friend's new phone number, but later that afternoon he could not find it or remember what he had done with it. a couple of days later, noah went back to the coffee shop, and while waiting in line, he suddenly remembered where he had put the phone number. this is an example of: