What causes the brownian motion of particles in a colloid? a) collisions between the particles and surrounding molecules b)interactions with rays of light that shine through the colloid c )the force of gravity, which pulls the particles downward d) electrical attractions between the particles and surrounding molecules

The correct answer option is a) collisions between the particles and surrounding molecules.

Explanation:

The collisions between the particles and surrounding molecules causes the Brownian motion of particles in a colloid.

Brownian motion is the irregular movement of the microscopic particles in a fluid which bombard into each other.

It basically is the result of the molecules of a dispersion medium colliding with the dispersed particles of the phase.

linda: 3 ; laura: 15

step-by-step explanation:

note that linda + laura's age is 18, and that linda is 12 years younger than her sister.

let "linda" = x , "laura" = y:

x + y = 18

x = y - 12

first, plug in y - 12 for x in the first equation:

(y - 12) + y = 18

simplify.

2y - 12 = 18

isolate the variable (y). note the equal sign, what you do to one side, you do to the other. do the opposite of pemdas. first add, then divide.

2y - 12 (+12) = 18 (+12)

2y = 18 + 12

2y = 30

(2y)/2 = (30)/2

y = 30/2

y = 15

next, plug in 15 for y in the second equation (the other equation would work too).

x = y - 12

x = (15) - 12

x = 3

linda's age is 3, laura's age is 15.

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