Part C - Elementary Mathematics
Vijay invests a sum of ₹5,400 and Mohan invests a sum of ₹9,400 at the same rate of simple interest per annum. If, at the end of 6 years, Mohan gets ₹600 more interest than Vijay, then find the rate of interest per annum (in percentage).
Find the total surface area of a solid hemisphere of radius 0.07 m. (Use π =\( \frac{22}{7} \))