Make h the subject of the relation V=1/3πr²h

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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?

Louis wants to carpet the rectangular floor of his basement.the basement has an area of 864 square feet.the width of the basement is 2/3 it's length. what is the length of louis's basement