I need help with #7. Please help. I have to show all work so please explain

Name the quadrilaterals that have four equal sides.

Which expression demonstrates the use of the commutative property of addition in the first step of simplifying the expression (-1+i)+(21+5i)+0

Answer asap. you begin with 1/2 scoop of ice cream. since you're hungry, you ask the vendor for 2/7 more scoops of ice cream. then, you eat 5/8 scoops. how many scoops of ice cream are left on your cone? i will mark brainliest for first correct answer.