Garry likes coffee and donuts. He is used to eating two donuts whenever he drinks one coffee. He never eats donuts without drinking coffee and the other way round. 

If we depict coffee on the horizontal axis and donuts on the vertical axis, what is the slope of Garry's indifference curve in the bundle of 2 coffees and 2 donuts? Please insert a numerical value only.

Peter consumes goods x and y and his indifference curves are described by the formula y = (k/2x)+2  (higher values of k correspond to better indifference curves). Peter strictly prefers the bundle (x,y)=(4, 6) to

Suppose that Juliet has CZK 490 to spend on milk and breakfast cereals. One bottle of milk costs CZK 30. Tesco offers a discount on breakfast cereals; the discounted price is CZK 60 for one cereal pack. However, one consumer might buy a maximum of 2 packs for the discounted price. If Juliet buys more, she pays an undiscounted price CZK 80 per pack. Suppose that Juliet buys 4 packs of cereals. How many bottles of milk could she afford to buy then?

Tony has income m and consumes good x and good y that have initial prices p_x and p_y. Suppose that p_x doubles and p_y triples while income remains constant. On a graph showing the budget line with good x on the horizontal axis and good y on the vertical axis,

Ann spends her entire income and consumes 6 packs of strawberries and 8 packs of oats. The price of strawberries is twice the price of oats per pack. Ann's income doubles and the price of strawberries packs triples, but the price of oats pack stays the same. If Ann buys 10 packs of oats, what is the maximum number of strawberries packs that she can afford?

Please, insert numerical value only.

Suppose that Lilly spends all of her income on baby spinach and broccoli (she has just learned that it is the perfect diet for her brain). She can just afford 11 packs of baby spinach and 4 broccolis per week. She could also use her entire income to purchase 3 packs of baby spinach and 8 broccolis per week. The price of one pack of baby spinach is CZK 30. What price does Lilly pay for one broccoli? Please, insert numerical value only.

Suppose that Frank buys bananas (x) and oranges (y). His budget line was described by the equation y=20-2x. At a later time, his budget line could be described by the equation y=30-x. What is a possible explanation for the change between the earlier and the later budget line?

Suppose that Juliet has CZK 400 to spend on milk and breakfast cereals. One bottle of milk costs CZK 25. Tesco offers a discount on breakfast cereals; the discounted price is CZK 60 for one cereal pack. However, one consumer might buy a maximum of 2 packs for the discounted price. If Juliet buys more, she pays an undiscounted price CZK 80 per pack. Suppose that Juliet buys 3 packs of cereals. How many bottles of milk could she afford to buy then?

Tony likes playing football and computer games. Playing football for 30 minutes and Minecraft for 20 minutes makes him as satisfied as playing football for 10 minutes and Minecraft for 50 minutes. Suppose that he plays Minecraft for 35 minutes now, and his preferences are convex.

Given only this information about Tony's preferences, what is the theoretical maximum time he could spend playing football to be as well off as in the previous two situations? Please insert a numerical value only.

Suppose that Eve spends all of her income on avocados and walnuts (she has just learned that it is the perfect diet for her brain). She can just afford 9 avocados and 10 packs of walnuts per week. She could also use her entire income to purchase 3 avocados and 12 packs of walnuts per week. The price of one avocado is CZK 20. How much is Eve's income per week? Please, insert numerical value only.