Answer
Length: 12 feet Width:4
Explanation
To get the area of a rectangle you times the length by the width
It says the length of the wall is 4 feet longer than TWICE it’s width since 12 times 4 is 48 and 12 is twice the amount of 4 plus 4 feet it fits the requirements of this question
There are 8 marks on the line and the first line is 3 long while the second is 2 long
c. 3/8+2/8=5/8
Answer: 
Step-by-step explanation:
Given
River is flowing from south to North with a velocity of 
Motor boat traverses the river from east to west at a speed of 
South component of boat velocity must compensate the river velocity in order to travel in west direction.

The answer would be 1/3. You have to work backwarda for this problem. You start off by subtracting 5/4 - 3/4 =2/4 which simplifies to 1/2. Then, you have to add 1/6. Using the greatest common denominator, you have 3/6 + 1/6=4/6 which simplifies to 2/3.