a. The amount of paper that he is going to need would given as 12 square inches.
b. If it is 11 inches what is needed to cover the wall is given as 396
We have the area of a rhombus to be given as
0.5 *d1 * d2
We have d1 = 6 inches
d2 = 4 inches
then area would be
0.5 * 6 * 4
= 12 inches
b. The amount of paper used as length is 11 feet long
1 ft = 12 inches
then 11 feet = 11 * 12
= 132
Number needed = 4
132/4 = 33
Then the area would be 33 * 12 inches to cover the wall
= 396
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