Hill

rectangle counting video watched

96-97 sprint

s11 need to know sum of first n squares. - n(n+1)(2n+1)/6

s12 green marbles should be g-15 for second equation, not g!

did s13

11 state solutions

https://artofproblemsolving.com/wiki/index.php/AMC_8_Problems_and_Solutions

89-90 school competition target 1 3/5; 2 96; both correct

89-90 school sprint

https://www.geeksforgeeks.org/hungarian-algorithm-assignment-problem-set-1-introduction/

in desmos can specify x range with curly brackets

y=e^{-x\ \left\{x\ge0\right\}}

y=2-e^{x\left\{x<0\right\}}