A researcher is trying to identify whether household substances are basic. Which approach would BEST help the researcher investigate whether substances are basic?
A. Observe each substance and record its color.
o B. Measure the temperature of each substance.
C. Test each substance with red litmus paper.
OD. Mix each substance with a weak base and record the results.

D

Step-by-step explanation:

It makes the most sense

C. Test each substance with red litmus paper.

Step-by-step explanation:

C is the correct answer because when you apply a base with a red litmus paper the outcome color should result in blue.

problem:

f(x) = - 2/3x + 5; f(5/2)

substitute 5/2 in for x:

f(5/2) = -2/3(5/2) + 5

simplify the right side:

f(5/2) = -5/3 + 5

f(5/2) = 10/3

f(5/2) = 10/3

i hope this !