Will the jars float or sink?

This task is about flotation.

jar-A.png

Air

jar-B.png

Water

jar-C.png

Sand

jar-D.png

Air

A student had four glass jars each with tight lids. The jars were full of either air, water, or sand. 
Each jar was put into a bucket of water.

Question 1Change answer

Select whether the jars would float or sink below.
 
i)   Jar A FloatSink
 
ii)  Jar B FloatSink
 
iii) Jar C FloatSink
 
iv) Jar D FloatSink