A). 50 penny
B) This type of battery is cost effective.
Explanation:
A) A pack of 8 batteries cost 3.99 pounds so one battery will cost = 3.99/8 = 0.499 pound
Since 1 pound = 100 penny
So 0.499 pound = 100×0.499 = 50 penny
B). A pack of 6 batteries of the same type costs 2.79 pounds
So one battery will cost = 2.79/6 = 0.465 pound or 47 penny
Now we say that type A batteries are costlier than B. Therefore B type batteries are of a better value.