How do you Find the value of the variable?

Volume of cylinder with a radius of 8cm and height of 25 cm

Ivan and jeff buy a package of 8 pens for $4.00. ivan wants 5 of the pens, and jeff wants 3.how much should each student pay?

Complete the table for different values of x in the polynomial expression -7x2 + 32x + 240. then, determine the optimal price that the taco truck should sell its tacos for. assume whole dollar amounts for the tacos.