Turbidity meter was used it experiment$($s$)$

a$)$ Turbidity

b$)$ Conductivity and turbidity

c$)$ Jar test and turbidity

d$)$ All of above

In calcium hardness experiment Sodium hydroxide was added to sample to:

a$)$ Precipitate out $Mg(OH{)}_2$

b$)$ Precipitate out $Ca(OH{)}_2$

c$)$ Adjusting $pH$ value

d$)$ Reducing error

Conductivity is defined as

a$)$ The ability of a substance to repel electric current.

b$)$ The ability of a substance to conduct electric current, which is the same as resistivity.

c$)$ The ability of a substance to conduct electric current, which is the reciprocal of resistivity

d$)$ The ability of a substance to conduct variable resistance,

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