If the sum of first 7 terms of an A. P is 49 and the sum of first 17 terms is 289 find the sum of first 30 term

The average human heart beats 1.15 \cdot 10^51.15⋅10 5 1, point, 15, dot, 10, start superscript, 5, end superscript times per day. there are 3.65 \cdot 10^23.65⋅10 2 3, point, 65, dot, 10, start superscript, 2, end superscript days in one year.how many times does the heart beat in one year? write your answer in scientific notation, and round to one decimal place.

The volume of a sphere is increased by 6%. calculate the corresponding percentage increased in it area.

Find the area of the regular hexagon if a side is 20 cm.