In the following structure, carbons (I),(2),(3) and (4) are classified respectively as

Carbon (i) : quaternary carbon

Carbon (ii) : secondary carbon

Carbon (iii) : tertiary carbon

Carbon (iv) : secondary carbon

Explanation:

Carbons can be classified into 4 categories:

(1) Primary carbon : These are the atoms where the carbon atom is attached to one other carbon atom.

(2) Secondary carbon : These are the atoms where the carbon atom is attached to two other carbon atoms.

(3) Tertiary carbon : These are the atoms where the carbon atom is attached to three other carbon atoms.

(4) Quaternary carbon : These are the atoms where the carbon atom is attached to four other carbon atoms.

In the given structure:

Carbon (i) is attached to 4 further carbon atoms and hence, it is a quaternary carbon.

Carbon (ii) is attached to 2 further carbon atoms and hence, it is a secondary carbon.

Carbon (iii) is attached to 3 further carbon atoms and hence, it is a tertiary carbon.

Carbon (iv) is attached to 2 further carbon atoms and hence, it is a secondary carbon.

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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