Remember that: irrational numbers repeat and cannot be put into fractions.
1) C or 1/2, Since it is expressed as a fraction you know it is rational.
2) D or sqrt 61, Well, it's not -5 since it's a whole number, basic multiplication tells you the square root of 36 is 6 which is also a whole number, and 2/3 is a fraction, so using process of elimination this is the only option left.
3) quotient Since rational numbers can be written as fractions, 1/4 is the same as dividing 1 by 4.
4) repeat As explained earlier, repeating decimals cannot be made into fractions, therefore not making them rational.
5) 0.375 3 divided by 8 is equal to 0.375.
I hope this helped you and have a great rest of your day!