Can someone explain how to solve please.

What is the point of inflection for the function f(x)=2cos4x on the interval (0, pi/2)

On the way home from visiting his family, vincent’s plane cruised at an altitude of 3.2 × 10^4 feet. he had heard that a man named felix baumgartner skydived from an altitude of 1.28 × 10^5 feet. vincent wants to know how much higher felix went on his skydiving trip. question 1 you have already seen how adding numbers works in either scientific notation or standard notation. but can you subtract numbers in scientific notation and get the same results as subtracting in standard notation? to find out, first solve vincent’s problem in standard notation. part a write the cruising altitude of vincent’s plane in standard notation.

Arace is 10 kilometers long.markers will be placed at the beginning and end of the race course and at each 500 meter mark.how many markers are needed to mark the course for the race?