HELP ME PLEASE i am not under standing the problem the instructions are on the attchment

What is the point of inflection for the function f(x)=2cos4x on the interval (0, pi/2)

The dance committee of pine bluff middle school earns $72 from a bake sale and will earn $4 for each ticket they sell to the spring fling dance. the dance will cost $400 write an inequality to determine the number, t of tickets the committee could sell to have money left over after they pay for this year's dance. what is the solution set of the inequality?

Carl is boarding a plane. he has 22 checked bags of equal weight and a backpack that weighs 4 \text{ kg}4 kg. the total weight of carl's baggage is 35 \text{ kg}35 kg.