The pile of balls (1)

Each point is in the centre of each ball.	What type of figure is ABCD?	a rectangle a rhombus a square	AB = cm
	What type of figure is ABCDS?	a pentagon a cuboid a right prism a pyramid	AS = cm

Using the Pythagorean theorem in the triangle ACB right-angled at B, AC²= As H is the middle of [AC], AH²=

Using the Pythagorean theorem in the triangle ASH right-angled at H, SH ²= SH ≈ cm  (to the nearest mm) The height of the pile is about  (to the nearest mm)