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John makes $10.50 pers hour what expression represens how much he will make if he works h hours

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?

How many sides does a regular polygon have if each exterior angle measure is 45 degrees explain your answer, i really don't understand this.