What’s the rate of change

Which of the following is true for the relation f(x)=2x^2+1

Kayla has a $500 budget for the school party.she paid $150 for the decorations.food will cost $5.50 per student. what inequality represents the number of students,s, that can attend the party?

At $1.32 million, they closed last month percent above what they paid in 2007." how much did they pay in 2007?