Coding Exercise: Gravity

A parcel is thrown downward at a speed of v m/s from an airplane at altitude 11000 m. As it falls, its distance from the ground is given by the formula -4.9t² - vt + 11000, where t is the time in seconds since it was dropped. Write a program to output the time it will take to reach the ground. The input to your program is the positive floating-point number v. The required time is given by the quadratic formula

Coding Exercise: Lucky Sevens

Write a program, using a for loop with step size 10, to print out all 2-digit numbers which end in 7, in increasing order.