The mathematical expression 9 ∈ t means: a.) 9 union tb.) 9 intersection tc.) 9 is an element of td.) 9 is not an element of t

The answer is the option C, which is: C.) is an element of .

The explanation of this answer is shown below:

In mathematics, the symbol ∈, which shown in the problem above, is used to express that an element belongs to a set.

As you can see above, the element 9 belongs to the set , therefore, is an element of , or: ∈.

24

step-by-step explanation:

i assuming that 2 sides are 6 the other 2 sides are 4 cm so 6 times 4 is 24 : )

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step-by-step explanation: