Question

density is mass per unit of volume. which pair of lab instruments would a student use to measure the density of seawater?
o a caliper and a flask
o a stopwatch and a beaker
o a balance and a beaker
o a meter stick and a temperature probe

Explanation:

To measure density ($
ho=\frac{m}{V}$), mass ($m$) and volume ($V$) are needed. A balance measures mass. A beaker can measure the volume of seawater (by reading the liquid - level markings). A caliper measures length/diameter (not for this density - related measurement). A stopwatch measures time. A meter - stick measures length. A temperature probe measures temperature. So, a balance (for mass) and a beaker (for volume) are the correct pair.

Answer:

C. a balance and a beaker