I got 9.75 hope it's right
Answer:

Step-by-step explanation:
Let E be the set of all even positive integers in the universe Z of integers,
i.e
E = {2,4,6,8,10 ....∞}
be the characteristic function of E.
∴

For XE(2)
since x is an element of E (i.e the set of all even numbers)
For XE(-2)
since - 2 is less than 0 , and -2 is not an element of E
For { x ∈ Z: XE(x) = 1}
This can be read as:
x which is and element of Z such that X is also an element of x which is equal to 1.
∴

E = {2,4,6,8,10 ....∞}
20 and 2
20 - 2 = 18
......................................
<h2>
The race is 1.2 miles long</h2>
Step-by-step explanation:
The first leg is 3/10 mi, the second leg is 1/2 mi, and the third leg is 2/5 mi.

Now we need to find length of race

The race is 1.2 miles long
Answer:
128
Step-by-step explanation: