Answer: option D
Step-by-step explanation:
The formulae for standard error = standard deviation/√n
But population standard deviation = 1.8 and sample size = n = 81
Standard error = 1.8/√81 = 1.8/9 = 0.2
Answer:

Step-by-step explanation:
Since interest is compounded semi-annually (half a year or 6 months), in a spawn of 2 years, the interest will have been compounded 4 times. As given in the problem, each time the interest is compounded, the new balance will be 107% or 1.07 times the amount of the old balance.
Therefore, we can set up the following equation to find the new balance after 2 years:

Answer:
Rs 448
Step-by-step explanation:
400 × 1.12 = 448
this a 12 % increase