Counting by Tens with numbers
10, 20, 30, 40, 50, 60, 70, 80, 90
Counting by Tens with words
ten, twenty, thirty, forty, fifty, sixty, seventy, eighty, ninety, one hundred
Number Patterns when counting by Tens
When you count by tens the numbers create a pattern. All the numbers end with a zero. The first digits are just like the numbers when you count (1, 2, 3, 4, 5, etc.). This pattern gives the numbers 10, 20, 30, 40, 50, etc.
found from: http://www.aaamath.com/k4c_cox1.htm
If Katie drew those chords and those line segments to form a square, then the diagonals would have to be congruent. The only way to have them would be through the center, therefore they must be diameters.
And if it is a square, then the diagonals are perpendicular bisectors meaning the angles would be right angles not acute or obtuse as in Choice D. <span />