3. B
4. A
5.A
6. A (i think)
Hope this helps
Answer: mass m = M·c·V
Explanation: M(CaCl2) = 110.98 g/mol, c= 0.15 mol/l,
n=m/M= cV, volume of Solution is not mentioned
Each step of the food chain in the energy pyramid is called a trophic level. Plants or other photosynthetic organisms (autotrophs) are found on the first trophic level, at the bottom of the pyramid. The next level will be the herbivores, and then the carnivores that eat the herbivores.
Answer: Thus molarity of
is 1.35 M
Explanation:
To calculate the volume of acid, we use the equation given by neutralization reaction:

where,
are the n-factor, molarity and volume of acid which is 
are the n-factor, molarity and volume of base which is KOH.
We are given:

Putting values in above equation, we get:

Thus molarity of
is 1.35 M