Complete the similarity proportion show steps

You have two cards with a sum of -12 in both hands. a. what two cards could you have? b. you add two more cards to your hand, but the total sum if the cards remains the same, (-12).

What is the size of the matrix resulting from

The ages of personnel in the accounting department of a large company are normally distributed with a standard deviation of 7 years. there is a 0.02275 probability that the age of any randomly chosen person in the department is less than 22 and 0.15866 probabilty that the age of any randomly chosen person is greater than 43. what is the mean of this distribution?