Answer:

Step-by-step explanation:
3x5=$15
15+10=$25 total to spend
He spends 12.75+8.5= $21.25
25-21.25=$3.75 left
Answer:
volume of cone=1/3 πr²h=1/3 ×π×5²×15=125πcm³
Let's go though the choices.
Major axis will get shorter. TRUE, CHECK ME
As the plane moves closer to the vertex the ellipse stays the same shape but shrinks.
Ellipse will become a circle. FALSE
As long as the plane is tilted, the ellipse can't be a circle.
Ellipse will degenerate to a point. TRUE, CHECK ME
Eventually the plane gets to the vertex, at which point (ha!) we have a single point.
Nappes? Is that a word? FALSE
The plane needs a steeper angle, steeper than the generators, before it can pass through both halves.
The generators are the lines through the vertex that form the cone. The plane isn't steep enough to hold any of them. FALSE
Answer: 200 meters per minute
Explanation: we know that she can run 100 meters per 30 seconds. the question is asking in terms of minutes, however. we have to convert the seconds into minutes. How many minutes is 30 seconds? well, 60 seconds are in a minute so 30 seconds are in half a minute. 30 seconds = .5 minutes.
Now, we have to find how many meters she runs per minute. this means how many meters she runs in one minute. we create a proportion:
100 meters/ .5 minutes = x meters / 1 minute
we cross multiply to get 100 = .5x
then, we simplify by dividing each side by .5 which equals
200=x