Please help me with this homework

What values of x satisfy the inequality x^2-9x< 0? how is your answer shown on the graph?

Jamie went to home depot. she bought 25 bags of soil that cost $9 per bag. she bought 15 pots at $8 each, and she bought 23 bags of pebbles at $15 each. she used a coupon that gave her $5 off for every 100 dollars she spent. how much did jame pay at the end?

Which equation can be used to measure the density of water in a spherical water tank? let w represent the number of water particles within the region.