Which expression fits this description?
The expression is the sum of two terms.
The first term is the product of 2 and a.
The second term is the quotient of b and 4.

The expression that fits the description is ;

(8a + b)/4

Step-by-step explanation:

Here, we want to find the expression that fits the given description;

We are told that the expression is a sum of two terms

The first term is 2 * a = 2a

The second term is the quotient ( result of division) of b and 4 = b/4

So the term we are looking for is;

2a + b/4 = (8a + b)/4

The answer is in the image 

The total nom of  code that can be used is equal to 5+3 = 8

The solution is in the following image

y=2x+15

where y=Value of coin

x=Age in years

Value of coin after 19 years=2*19+15

=$53

Therefore, Value after 19 years=$53

The answer is in the image 

The solution is given in the image below

Speed=Distance/time

Here,

distance=15m

time=1sec

speed=15/1=15m/sec

Distance=Speed*time

time=15min=15*60sec=900sec

Distance travelled in 15 min=15*900=13,500m

=13500/1000 km=13.5Km

The wood before starting =12 feet

Left wood=6 feet

Wood used till now=12-6=6 feet

Picture frame built till now= 6/(3/4)

=8 pieces

Therefore, till now 8 pieces have been made.

The answer is in the image