How many nonisomorphic simple graphs are there with six vertices and four edges?

Nikolas calculated the volume of the prism. his work is shown below.

Jada has a meal in a restaurant she adds up the prices listed on the menu for everything they ordered and gets a subtotal of $42.00. when the check comes, it says they also need to pay $3.99 in sales tax. what percentage of the subtotal is the sales tax

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