Fred is playing the slot machines. after a certain number of plays, he wins a few coins, but fred is unable to determine how many plays he needs to win. which of the following statements is true? a. fred is on a fixed-interval schedule of reinforcement. b. fred is on a variable-interval schedule of reinforcement. c. fred is on a fixed-ratio schedule of reinforcement. d. fred is on a variable-ratio schedule of reinforcement.

In a closed system, the total energy prior to an energy transformation is the total energy after. a. equal to b. unrelated to c. greater than d. less than

Idon’t quite understand this problem

The dipole moment of the water molecule (h2o) is 6.17x10^-30 c.m. consider a water molecule located at the origin whose dipole moment p points in the +x-direction. a chlorine ion ( of charge-1.60x10^-19c , is located at x=3.00x10^-9m . assume that is much larger than the separation d between the charges in the dipole, so that the approximate expression for the electric field along the dipole axis can be used. a) find the magnitude of the electric force that the water molecule exerts on the chlorine ion. b) what is the direction of the electric force. -x-direction or +x-direction c) is this force attractive or repulsive?