PLEASE HELP What is the Force of a bike rider with a mass of 45 kg, accelerating 7 m/s^2

What is the difference between electrically neutral objects and electrically charged objects

How is the gravitational force related to the distance between two objects?

What is the electric force acting between two charges of -0.0045 c and -0.0025 c that are 0.0060 m apart? use fe=kq1q2/r^2 and k = 9.00 x 10^9 n*m^2/c^2 a. 1.7 x 10^7 n b. -1.7 x 10^7 n c. -2.8 x 10^9 n d. 2.8 x 10^9 n