1) Formulate the situation as a system of two linear equations in two variables. Be sure to state clearly the meaning of your x- and y-variables. Solve the system by the elimination method. Be sure to state your final answer in terms of the original question.

A lawyer has found 60 investors for a limited partnership to purchase an inner-city apartment building, with each contributing either $4,000 or $8,000. If the partnership raised $324,000, then how many investors contributed $4,000 and how many contributed $8,000?

2) A jar contains 80 nickels and dimes worth $7.30. How many of each kind of coin are in the jar?

3) The concession stand at an ice hockey rink had receipts of $6600 from selling a total of 2800 sodas and hot dogs. If each soda sold for $2 and each hot dog sold for $3, how many of each were sold?

4) For the final days before the election, the campaign manager has a total of $29,000 to spend on TV and radio campaign advertisements. Each TV ad costs $3000 and is seen by 10,000 voters, while each radio ad costs $500 and is heard by 2000 voters. Ignoring repeated exposures to the same voter, how many TV and radio ads will contact 104,000 voters using the allocated funds?