Answer:
a and d are both true. The rest are not.
Explanation:
1 and 6 are like terms. They are both integers. They can be combined. This statement is true.
7 is a numerical coefficent. This statement is true.
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The others are all false for one reason or another
b is false. The factor is made up of 2 terms not 3. 7a is one term.
c is false. "a" is a variable. So the whole term can be anything.
e is false. 7a + 2 is a factor
f is false. There are two true statements.