Suppose there are two risky assets: Security 1 has expected return of 15% and standard dev

iation of 20%, security 2 has expected return of 10% and standard deviation of 25%, and the correlation of security 1 with security 2 is 0.90. Calculating the expected return and standard deviation of portfolio with security 1 and security 2 when the weight of security 1 is 1.8.

A、The expected return is 0.09 and standard deviation is 0.265

B、The expected return is 0.19 and standard deviation is 0.288

C、The expected return is 0.2 and standard deviation is 0.23

D、The expected return is 0.19 and standard deviation is 0.2

iation of 20%, security 2 has expected return of 10% and standard deviation of 25%, and the correlation of security 1 with security 2 is 0.90. Calculating the expected return and standard deviation of portfolio with security 1 and security 2 when the weight of security 1 is 0.4.

A、The expected return is 0.09 and standard deviation is 0.265

B、The expected return is 0.075 and standard deviation is 0.288

C、The expected return is 0.12 and standard deviation is 0.225

D、The expected return is 0.12 and standard deviation is 0.265

iation of 20%, security 2 has expected return of 10% and standard deviation of 25%, and the correlation of security 1 with security 2 is 0.90. What are the expected return and standard deviation of portfolio with security 1 and security 2 when the weight of security 1 is -0.5?

A、The expected return is 0.09 and standard deviation is 0.265

B、The expected return is 0.075 and standard deviation is 0.288

C、The expected return is 0.12 and standard deviation is 0.225

D、The expected return is 0.12 and standard deviation is 0.265

iation of 20%, security 2 has expected return of 10% and standard deviation of 25%, and the correlation of security 1 with security 2 is 0.90. Calculating the expected return and standard deviation of portfolio with security 1 and security 2 when the weight of security 1 is 0.8.

A、The expected return is 0.14 and standard deviation is 0.265

B、The expected return is 0.14 and standard deviation is 0.206

C、The expected return is 0.12 and standard deviation is 0.225

D、The expected return is 0.12 and standard deviation is 0.265

iation of 20%, security 2 has expected return of 10% and standard deviation of 25%, and the correlation of security 1 with security 2 is 0.90. Calculating the expected return and standard deviation of portfolio with security 1 and security 2 when the weight of security 1 is 2.5.

A、The expected return is 0.15 and standard deviation is 0.265

B、The expected return is 0.2 and standard deviation is 0.023

C、The expected return is 0.225 and standard deviation is 0.25

D、The expected return is 0.225 and standard deviation is 0.23

Suppose there are two eventsand. If, thenandcan not be independent.

Suppose there are three events,, and. Ifandare independent,andare independent, andandare independent, then,, andare jointly independent.

Suppose there are two eventsand. Ifand, then.

Suppose you just signed a Purchase and Sale Agreement on a new house and you have three choices based on the expectation of the variation of interest rates in the future: (1) Interest rates have been falling, so fixed-rate loans are now very attractive. You could lock in a fixed rate of 7% (annual percentage rate, APR) for 30 years (2) Interest rates are falling, so you are thinking about a 30-year variable-rate loan, which is currently at 4.5% and which is tied to the floating interest rates of Treasury bill (3) A variable-rate loan that begins at 5% and can increase by only as much as 2% per year up to a maximum of 11% If you wanted to hedge all risk of interest rate exposure, you should choose the plan of ( ), if you wanted to transfer risk through insuring, you should choose the plan of ( ).

A、(1); (2)

B、(1); (3)

C、(2); (3)

D、(1); (2) and (3)

There are three kinds of memory: sense memory, working memory, and long-term memory. Think of them as three connected rooms in which you store different kinds of memories.

The first kind of memory is sense memory. Everything you are sensing right now is stored here. Perhaps you feel the sun on your face or smell the aroma(香味) of food. Sense memories last only a few seconds, but they connect one moment to the next. They give your life a flow, even though they are quickly forgotten.

You keep a few items(条目) in working memory. These are memories you need for what you are doing. Suppose you look up a friend's telephone number in the phone book. You'll probably remember the number for a little while. But if you get distracted (分神), you might quickly forget it. A memory usually stays in your working memory for just a few days at most. Working memory has another limit, too. Only a small number of items fit into it at any given time.

Memories you want to keep for a long time go into your long-term memory. They can stay with you all your life. In long-term memory, you can store a huge number of items. Can you re member how to play your favorite game? Do you recall your first birthday party? If so, you are bringing up memories that are stored in your long-term memory. Sometimes, people have trouble finding a particular long-term memory. Have you ever struggled to remember a familiar name or fact? When this happens, people sometimes say the information is "on the tip of the tongue. "

Which of the following best describes the sense memory?

A．It's your preference for certain food.

B．It's something you did a while ago.

C．It's a memory of the distant past.

D．It's an immediate memory.