The fact that they want a variable expression means that they don't want a specific answer to the problem. The want an expression with an unknown (like x or y) that they can plug in a number if they wanted to solve an equation...
1. The cost of y roses. Well it tells us that the roses cost $1.60 each. So if we bought 1 we would multiply it by 1.60 to find the cost. If we bought 50 we would multiply 50 x 1.60. Since the number of roses can change we call it a variable and we can replace it with x or y (or anything else for that matter). Since we have a variable, we can put whatever number we want into it to solve the equation. So to get back to your problem, the cost of y roses would be...
$1.60y that just means it will cost 1.60 x number of roses
2. Cost of 12 carnations. In this case we know how much the carnations cost and how many we buy so we just multiply...
12 x 1.15 = $13.80
3. The cost of m roses and f carnations That's "some number" of roses and "some number" of carnations. Roses are $1.60 so $1.60m and carnations are $1.15 so $1.15f. We are buying both so add them together...
here you guess and judge by your basic knowledge of angles and guess the angle measurement. and as far as the angle names with three points there should be three names and so the angle you are measuring must always be in the middle and ya :))
