Answer:
(6, -8)
Step-by-step explanation:
big brain
Answer:
The answer is option 3.
Step-by-step explanation:
You have to substitute H+=2×10^(-9) into the equation of pH :
pH = -log[H+]
H+ = 2×10^(-9)
pH = -log[2×10^-9]
= 8.70 (3s.f)
Let the marks of the students in class 1 be
the average of these 12 marks is 90, so
which means
similarly, let
be the marks of the students in the second class,
so
which means
The 32 students averaged:
The sum means addition
v + 3