Agroup of several electric cells connected together is called
a. a recharger.
c. an electrode.
b. a battery.
d. an electrolyte. 8

correct answer is option b (A group of several electric cells connected together is called a battery)

Explanation:

Recharger:

Recharger is a device which is used to recharge a battery.

Electrode:

Electrode is a terminal of cell . It may be positive terminal (anode) or it may be negative terminal cathode

Battery

Battery is a device which consists of group of 2 or more cells which are connected with each other.

electrolyte:

An electrolyte is a type of an electric conductor which consists of chemical compound which get break into ions and  due to movement of ions electric conduction takes place.

so correct answer is option b (A group of several electric cells connected together is called a battery)

can be answered using momentum.

momentum = p

p1= mass1 * velocity1

p1 = p2

therefore

p1 = 6kg * 4m/s

p1 = 24kgm/s

p2=m2 * v2

24 kgm/s = 7kg * v2

v2 = 24 kgm/s / 7kg

v2= 3.42 m/s

your answer is c! hope this : )