What is a public key infrastructure? select one: a. a structure that provides all of the components needed for entities to communicate securely and in a predictable manner b. a structure that enables secure communications in chat rooms, instant messaging, and text messaging c. is a method of securing communications through the use of a single shared key d. a structure that enables parties to use communications such as email?

On february 3, smart company sold merchandise in the amount of $5,800 to truman company, with credit terms of 2/10, n/30. the cost of the items sold is $4,000. smart uses the perpetual inventory system and the gross method. truman pays the invoice on february 8, and takes the appropriate discount. the journal entry that smart makes on february 8 is:

Consider the following limit order book for a share of stock. the last trade in the stock occurred at a price of $50. limit buy orders limit sell orders price shares price shares $49.75 500 $49.80 100 49.70 900 49.85 100 49.65 700 49.90 300 49.60 400 49.95 100 48.65 600 a. if a market buy order for 100 shares comes in, at what price will it be filled? (round your answer to 2 decimal places.) b. at what price would the next market buy order be filled? (round your answer to 2 decimal places.) c. if you were a security dealer, would you want to increase or decrease your inventory of this stock? increase decrease

Suppose a firm faces a fixed price of output, 푝푝= 1200. the firm hires workers from a union at a daily wage, 푤푤, to produce output according to the production function 푞푞= 2퐸퐸12. there are 225 workers in the union. any union worker who does not work for this firm is guaranteed to find nonunion employment at a wage of $96 per day. a.what is the firm’s labor demand function? b.if the firm is allowed to choose 푤푤, but then the union decides how many workers to provide (up to 225) at that wage, what wage will the firm set? how many workers will the union provide? what is the firm’s output and profit? what is the total income of the 225 union workers? c.now suppose that the union sets the wage, but the firm decides how many workers to hire at that wage (up to 225). what wage will the union set to maximize the total income of all 225 workers? how many workers will the firm hire? what is the firm’s output and profit? what is the total income of the 225 union workers? [hint: to maximize total income of union, take the first order condition with respect to w and set equal to 0.]