Rashad is filling a toy box that are each a unit cube size. he filled the bottom layer of a toy box with 15 wooden blocks. he then stacked two more wooden blocks on top of the bottom layer. the partially filled is shown below

c.

step-by-step explanation:

she should of added 9^2 and 12^2. that is because it is a^2+b^2=c^2. c^2 is the hypotenuse and should always be bigger than the other two numbers. which is why she should of added 9 squared and 12 squared together instead of 15 squared.